Hindawi Publishing CorporationGastroenterology Research and PracticeVolume 2013 Article ID 393015 8 pageshttpdxdoiorg1011552013393015

Review ArticleHelicobacter pylori-Induced Chronic Gastritis andAssessing Risks for Gastric Cancer

Gonzalo Carrasco1 and Alejandro H Corvalan2

1 Department of Pathology Mount Sinai School of Medicine 1425 Madison Ave New York NY 10029 USA2Centre for Translational Research in Oncology (CITO) and Department of Hematology and OncologyPontificia Universidad Catolica de Chile Marcoleta 391 8330074 Santiago Chile

Correspondence should be addressed to Alejandro H Corvalan corvalanmedpuccl

Received 27 December 2012 Accepted 25 February 2013

Academic Editor N Ananthakrishnan

Copyright copy 2013 G Carrasco and A H Corvalan This is an open access article distributed under the Creative CommonsAttribution License which permits unrestricted use distribution and reproduction in any medium provided the original work isproperly cited

Chronic gastritis is an inflammation of the gastric mucosa and has multiple etiologies Here we discuss the pathological alterationsinduced by Helicobacter pylori (HP) leading to chronic gastritis and the epigenetic bases underlying these changes We review thehistology of the normal gastric mucosa and overview the role of HP in the multistep cascade of GC We attempt to define therole of the Operative Link for Gastritis Assessment (OLGA) staging system in assessing the risk of GC The epigenetic bases ofchronic gastritis mainly DNA methylation are presented through examples such as (i) the methylation of the promoter regionof E-cadherin in HP-induced chronic gastritis and its reversion after HP eradication and (ii) the association of methylation ofthe promoter region of Reprimo a p53-mediated cell cycle arrest gene with aggressive HP strains in high risk areas for GC Inaddition we discuss the finding of RPRM as a circulating cell-free DNA offering the opportunity for noninvasive risk assessmentof GC Finally the integration of OLGA and tissue biomarkers by systems pathology approach suggests that severe atrophy has agreater risk for GC development if in addition overexpressed p73 This trial is registered with ClinicalTrialsgov NCT01774266

1 Introduction

Since 1870 both human and veterinary pathologists havedescribed bacterial infections based on the observation oftiny curved bacteria within gastric mucosa [1 2] Howeverthese organisms were dismissed as irrelevant contaminantsIn 1947 when gastroscopy was first being used Schindlerdeemed gastritis as ldquoone of the most debated diseases of thehuman bodyrdquo and predicted that its significance would bediscussed ldquofor some time to comerdquo [3] Schindler himselfclaimed that the ldquobacteriological etiology of chronic gastritishas not been convincingly proved in a single caserdquo [3] In 1984Marshall and Warren proposed that chronic ldquoidiopathicrdquogastritis had a bacterial cause that is Helicobacter pylori [4]Their hypothesis was met with great skepticism Howeverwithin a few years the association betweenH pylori gastritispeptic ulcer and gastric cancer came to be acknowledgedand ultimately accepted [4] For the purpose of this paperwe will focus mainly on the cascade of events produced byHelicobacter pylori infection leading to chronic changes in the

gastric mucosa and the risk assessment for the developmentof gastric cancer In addition we will explore the epigeneticbases that underlie the changes of chronic gastritis

2 Normal Gastric Histology

In order to recognize pathologic tissue responses in gastritisit is essential to know the spectrum of normal gastric mucosahistology patterns Normal gastric mucosa is formed by theepithelialglandular and lamina propria components Theepithelial component consists of the foveolar epitheliumwhich is formed by tall columnar mucous cells with basallysituated nuclei and supranuclear collections of closely packedsmall mucus globules that discharge their content ontothe surface forming an adherent protective lubricant layerthat lines the lumen The glandular component changesdepending on its location in the stomach

(1) Cardiac glands are limited to a narrow region of thestomach (the cardia) that surrounds the esophageal

2 Gastroenterology Research and Practice

(a) (b)

Figure 1 Normal gastric mucosa histology ((a) HampE 10x square 40x) Fundic glands are simple branched tubular glands that extend fromthe bottom of the gastric pits to themuscularis mucosae themore distinctive cells are parietal cells ((b) HampE 10x square 40x) Antral mucosais formed by branched coiled tubular glands lined by secretory cells similar in appearance to the surface mucus cells

orifice They are tubular somewhat tortuous andoccasionally branched and are mainly formed bymucus-secreting cells with occasional interspersedenteroendocrin cells

(2) Fundic glands are present throughout the entiregastric mucosa except for relative small regionsoccupied by cardiac and antral-pyloric glands Thefundic glands are simple branched tubular glandsthat extend from the bottom of the gastric pits tothemuscularis mucosae (Figure 1) and are formed byfour functional types of cells mucous neck cells chiefcells enteroendocrine cells parietal cells (also calledoxyntic cells) and undifferentiated cells

(3) Antral-pyloric glands are located in the pylori antrum(the part of the stomach between the fundus andthe pylorus)They are branched coiled tubular glandsand are lined by secretory cells similar in appearanceto the surface mucus cells (Figure 1) suggesting arelative viscous secretion Enteroendocrine cells arefound interspersed within the gland epithelium alongwith occasional parietal cells

The lamina propria is relatively scant and restricted to thelimited spaces surrounding the gastric pits and glands Thestroma is composed of reticular fibers with associated fibrob-lasts and smooth muscle cells It is also composed of lym-phocytes plasma cells macrophages and some eosinophilsThe lymphocytes are predominantly immunoglobulin (Ig)A-producing B cells IgG- and IgM-secreting cells are alsopresent Under normal conditions intraepithelial lympho-cytes are not present anywhere in the gastric mucosa Thereis also a small number of lamina propria T cells neutrophilsand mast cells The lamina propria also contains capillariesarterioles and nonmyelinated nerve fibers Small lymphoidaggregates usually located in close proximity to the muscu-laris mucosae at the base of the lamina propria especially atthe corpus could be present in normal gastric mucosa Incontrast the presence of lymphoid aggregates with germinalcenters is extremely rare in the mucosa of normal H pylorinegative adults [5]

3 Histopathology of Helicobacterpylori-Induced Chronic Gastritis

H pylori is a microaerophilic gram-negative bacteria Theearly phase of H pylori infection elicits an acute inflamma-tory response that is either asymptomatic or symptomaticwith short-lived clinical manifestations such as nausea andvomiting that evolve to a long-standing chronic gastritis [4]Its prevalence goes from less than 15 in some populationsto virtually 100 depending on socioeconomic status andcountry development [6] In industrialized countries (West-ern Europe United States Canada and Australia) exposuretends to occur later in life which results in a lower percentageof infected adults An average of 20 to 30 of adults isinfected by age 50 [6] and the prevalence ofH pylori infectionhas been steadily declining in emerging countries which isprobably a reflection of improved sanitary conditions as wellas the widespread use of antibiotics The foveolar epitheliumproduces a thick layer of mucus that plays a protective roleThis mucus layer is the primary site forH pylori colonization[7] so they characteristically attach to the surface mucouscells but do not penetrate them In chronic infection Hpylori contacts the surface epithelial membrane producingprominent epithelial degeneration [8 9] The cells oftenbecome irregular and cuboidal in shape showing a decreasein apical mucin content as well as occasional ldquodrop outsrdquowhich leaves small gaps in the epithelium and contributes toa ragged disorderly appearance

H pylori preferentially colonize the antrum but theymayinfect any part of the stomach where it causes gastritis Whentreated the bacteria migrate from the antrum to the corpusdecreasing the activity of antral gastritisMarked neutrophilicinfiltrates appear in the mucous neck region and laminapropria in early acute gastritis (Figure 2) when severe theyaggregate in the pit lumens to form pit abscesses Both theneutrophils and theH pylori destroy the epithelium causingthe mucous neck cells to proliferate in an effort to replacethe dying cells The regenerative pit bases are characterizedbymucin loss cytoplasmic basophilia increasedmitoses andhyperchromatic nuclei that are sometimes severe enough tomimic dysplasia

Gastroenterology Research and Practice 3

(a) (b)

Figure 2 Early acute superficial gastritis ((a) HampE 20x) Marked neutrophilic infiltrates appear in the mucous neck region and lamina witha pit micoabscess ((b) H pylori immunostaining rabbit polyclonal clone CH-20 429 Novocastra 40x) Numerous H pylori bacteria arepresent in the superficial foveolar epithelium

Neutrophilic inflammation and the presence of lymphoidfollicles with germinal centers are the two most distinctivehistological features ofH pylori infection and its eradicationcauses rapid neutrophil disappearance thus their continuedpresence is considered a valuable indicator of therapeuticfailureThe surface changes reverse rapidly and the epithelialcells acquire their normal shape and spatial organizationwithin a few days of H pylori eradication However anyatrophy that had developed remains as did the lymphoidaggregates [10] These features become permanent compo-nents of the once-infected gastric mucosa

4 Grading the Helicobacterpylori-Induced Chronic GastritisThe Updated Sydney System

The most widely used grading system for gastritis is theUpdated Sydney System [11] The system provides guidelinesfor generating systematic and uniform diagnostic reportsThe goal of the Sydney System is to make gastric biopsypathology reporting consistent so that clinical studies canbe performed and evaluated in a meaningful manner Thesystem classifies chronic gastritis on the basis of topographymorphology and when possible etiology into three broadcategories acute chronic and special (or distinctive) Thebiopsy protocol recommends that specimens from threecompartments (ie antrum incisura angularis and cor-pus) should be separately designated when submitted tothe pathology laboratory Each relevant pathologic feature(density of H pylori intensity of neutrophilic and mononu-clear inflammation atrophy of the antrum and corpus andintestinal metaplasia) should be graded on a standardizedvisual analogue scale (Figure 3) Each feature is assignedeither a numeric or descriptive value 0 for absent 1 formild 2 for moderate and 3 for marked (or severe) Thevalues of each specimen are then averaged separately for eachanatomic compartment (antrum and corpus) The next stepis to document the degree of inflammation in the two maingastric compartments (antrum and corpus) and to deter-mine whether the inflammation is similar in intensity (ie

pangastritis) or more severe in either the antrum (antrum-predominant gastritis) or the corpus (corpus-predominantgastritis)

5 Helicobacter pylori-InducedChronic Gastritis and Multistep Cascade ofGastric Carcinogenesis

In gastric cancer development H pylori-induced chronicgastritis is the first step of the so-called multistep cascadeof gastric cancer The cascade sequence of gastric carcino-genesis includes the nonatrophic chronic gastritis multifocalatrophic gastritis intestinal metaplasia low-grade dyspla-sia (low-grade noninvasive neoplasia) high-grade dysplasia(high-grade noninvasive neoplasia) and invasive adenocarci-noma as described by Correa as the ldquohuman model of gastriccarcinogenesisrdquo [12] This multistep model hypothesizes thatthe sequence of lesions reflects a dynamic process from anaıve inflammation caused by H pylori infection to a fullymalignant neoplasm of the stomach [13ndash16] Independentepidemiological studies have confirmed that these entitiesare all linked through a sequential cause-effect relationshipthus supporting the concept of a human model for gastriccarcinogenesis [17ndash19] In a recent review and update of thismodel it is also postulated that H pylori is present not onlyin the first step of gastric mucosa inflammation but as anetiological factor in every step of the precancerous cascade[20] In the first step H pylori infection targets normalmucosa withwell-preserved gastric glands by definition suchgastritis is nonatrophic At this point it can be cured byclearing H pylori infection or it may be evolving in twoways it can remain as nonatrophic or it progresses in severityleading to damage to the gastric glands whichmay eventuallydisappear [20] The progression depends on the interplay ofthree sets of etiological factors infectious agent hostrsquos geneticsusceptibility and external environment these determinethe susceptibility and severity of outcome in the subset ofindividuals that develop clinical disease [20 21]The presenceof virulent factors in the infecting H pylori strain is a knowndeterminant factor of the outcome of the infection Infection

4 Gastroenterology Research and Practice

Normal Mild Moderate Marked Normal Mild Moderate Marked

Atrophy antrum

Neutrophils

Mononuclear cells

Atrophy corpus

Intestinal metaplasia

H pylori

Figure 3 The Updated Sydney System visual standardized visual analogue scale Each feature is assigned either a numeric or descriptivevalue 0 for absent 1 for mild 2 for moderate and 3 for marked (or severe) Taken from Dixon et al [11]

Normal gastric mucosa

Non-atrophic gastritis

Non-atrophic gastritis

Duodenal ulcer

Multifocalatrophic gastritis

Intestinalmetaplasia

Dysplasia

Cancer

H pylori

cagAminus

vacA s2m2

cagA+

vacA s1m1

Figure 4 Multistep cascade of gastric cancer This sequence begins with the infection of H pylori to sequential steps of the precancerouscascades Taken from Correa and Piazuelo [20]

with cag-positive vacA s1m1 strains is associated with thedevelopment of gastric cancer while cag-negative vacA s2m2infection does not increase the risk of cancer and is associatedto the persistency of nonatrophic gastritis (Figure 4) [20 22]

6 Assessing Risks forGastric Cancer The Operative Link forGastritis Assessment (OLGA)

The risk ofmalignant transformation of the lesions associatedwith the multistep cascade of gastric cancer is poorly definedLong-term follow-up studies have shown a risk from 10 to17 in the case of dysplasia [23ndash27] For intestinalmetaplasiathe risk assessment has conflicting results and thereforea limited clinical value [28ndash32] The recently developedOperative Link for Gastritis Assessment (OLGA) stagingsystem [33] through the evaluation of the extension and

site of the atrophic changes is an attempt to evaluate therisk of chronic gastritis to progress to intestinal metaplasiaand gastric cancer [34ndash36] Long standingH pylori infectionmay lead to the loss of functional glands (atrophy) andreplacement of the normal gland and foveolar epitheliumby intestinal type cells (intestinal metaplasia) (Figure 5) thetwo main histological abnormalities invariable present as thebackground of gastric cancer [37] The extent and site ofthe atrophic changes significantly correlate with cancer risk[38] Two main types of atrophy can be recognized onecharacterized by the loss of glands accompanied by fibrosisor fibromuscular proliferation in the lamina propria andthe other characterized by the replacement of the normal(native) glands with metaplastic glands (ie glands that donot normally belong to that area) [39] The degree of atrophyand metaplasia can be assessed with OLGA staging systemfor atrophy risk assessment [33] This new system requiresthat specimens are taken according to the biopsy protocol

Gastroenterology Research and Practice 5

(a) (b)

Figure 5 Atrophy is the loss of appropriate glands ((a) HampE 10x) Antral gastric mucosa with accentuated atrophy because replacementby extensive intestinal metaplasia ((b) HampE 10x square 20x) Fundic-corporal gastric mucosa with extensive loss of gastric glands partiallyreplaced by pseudo-pyloric metaplasia

Table 1TheOLGA staging frame Atrophy is scored as the percentage of atrophic glands and scored on a four-tiered scale No atrophy (0) =score 0 mild atrophy (1ndash30) = score 1 moderate atrophy (31ndash60) = score 2 9 severe atrophy (gt60) = score 3These scores (0ndash3) are usedin the OLGA staging assessment in each 10 compartment Taken from Rugge et al Dig Liver Dis 2011 43S373-84 with permission of Elsevier

CorpusAtrophy score No atrophy Mild atrophy Moderate atrophy Severe atrophy

(score 0) (score 1) (score 2) (score 3)

Antrum

No atrophy (score 0)(including incisura angularis) Stage 0 Stage I Stage II Stage II

Mild atrophy (score 1)(including incisura angularis) Stage I Stage I Stage II Stage III

Moderate atrophy (score 2)(including incisura angularis) Stage II Stage II Stage III Stage IV

Severe atrophy (score 3)(including incisura angularis) Stage III Stage III Stage IV Stage IV

of the Sydney System and that atrophy is scored in a four-tiered scale (0ndash3) according to the visual analogue scale of theHouston-updated Sydney system The stage resulting fromthe combination of atrophic changes was assessed in the twomucosal compartments considered herein (Table 1)

7 Assessing Risks for Gastric CancerThe Epigenetic Bases of Chronic Gastritis

The molecular bases of the multistep process of gastriccarcinogenesis are highly relevant since it contributes greatlyto assess risks of gastric cancer Therefore chronic gastritisshould be understood as a disturbance in the balance betweentumor suppressor genes and oncogenes Many tumor sup-pressor genes have been identified in gastric cancer as wellas chronic gastritis [40] For example inactivation of p53tumor suppressor gene E-cadherin and DNA mismatchrepair genes (hMSH2 and hMLH1) responsible for loss ofheterozygosity (LOH) andmicrosatellite instability (MSI) arewell-recognized examples However multiple studies haveshown that mutation andor deletion is an infrequent mecha-nism of inactivating these well-established tumor suppressorgenes [41] In this scenario epigenetic alterations such as

DNA methylation have been proposed as an alternativemechanism for inactivation of tumor suppressor genes [41]DNA methylation is a process in which cytosines acquirea methyl group in 51015840 position only if they are followedby a guanine (CpG site) [42] Since DNA methylation hasbeen considered as an excellent candidate to explain howenvironmental factors may increase the risk of cancer ithas been proposed as a key element for the early events ofgastric carcinogenesis [43] For example Chan et al [44]found that DNA methylation of the promoter region of E-cadherin has been associated with H pylori infection Thisassociationwas independent of the age andor type of gastritis[44] Furthermore the same authors [45] also demonstratethat H pylori eradication with antibiotics reverses the DNAmethylation of E-cadherin (Figure 6) Similarly Maekita etal [46] analyzed the effect of H pylori infection on DNAmethylation for multiple genes (HAND1 HRASLS LOXp16 P41ARC and THBD) in H pylori negative and positivehealthy donors and gastric cancer patients Among healthydonors methylation levels were higher in H pylori positivesthan in H pylori negatives [46] Taken together these datasuggest that H pylori infection induces DNA methylationmostly in premalignant conditions rather than gastric canceritself [46] Among other tumor suppressor genes inactivated

6 Gastroenterology Research and Practice

Week 0Control Patient 1 Patient 2 Patient 3 Patient 4 Patient 5 Patient 6

MW U M U M U M U M U M U M U M

(a)

Week 0T ATGCGAGG TC GGG TGGGTGGGTCGTTAGTTT CG TTT T

(b)

Week 6Control Patient 1 Patient 2 Patient 3 Patient 4 Patient 5 Patient 6

MW U M U M U M U M U M U M U M

(c)

Week 6T GA TT G GT TGT GG T T GGT AGGT G AA TT T T TAG

(d)

Figure 6 CpG island methylation pattern at the E-cadherin gene in gastric mucosa from patients with dyspepsia (a) Before eradicationof H pylori (week 0) methylation was present in patients 3 5 and 6 (b) The methylated product was confirmed by sequencing using thesame methylated primer (c) After eradication of H pylori (week 6) methylation was not present in any patient (d) The methylated productwas again confirmed by sequencing using the same methylated primer No methylated cytosine was seen MW molecular weight marker Uunmethylated band M methylated band red color unmethylated cytosines converted to thymidine blue color methylated cytosines Takenfrom Chan and Rashid [45]

Controls NTAMs

p73

ATR-3IM-3CI-3OLGA stage-3OLGA stage-4

IM-0

ATR-0

CI-0

OLGA stage-0

Figure 7 Serial analysis formicroarray fromnontumor adjacentmucosa (NTAM) and chronic gastritis controls NTAMgroup is significantlycharacterized by the overexpression of p73 OLGA stages III to IV and severe atrophy (ATR-3) intestinal metaplasia (IM-3) and chronicinflammation (CI-3) according to the Sydney System Control group cases were significantly characterized by lack of intestinal metaplasia(IM-0) atrophy (ATR-0) and chronic inflammation (CI-0) False discovery rate = 0 Taken from Carrasco et al [51]

by DNAmethylation Reprimo (RPRM) a downstreammed-iator of p53-induced G2 cell cycle arrest [47] has beenrecently associated with more aggressive H pylori strains(cag-positive vacA s1m1 and EPIYA polymorphisms) inColombian residents from areas with high incidence ofgastric cancer [48] Furthermore we have identified thatDNA methylation of RPRM is not only found in gastricmucosa but also in the plasma of gastric cancer patients[49] Therefore this circulating cell-free DNA offers theopportunity for noninvasive assessing risks for gastric cancerSince a recent meta-analysis suggests that among severalcandidates circulating cell-free DNA of RPRM methylationis the most promising [50] this issue is currently underevaluation (Detection of Methylated Reprimo in Plasma forAsymptomatic Gastric Cancer DEMRAC study Finally we

have recently attempted to identify specific tissue biomarkersfor assessing the risk of premalignant gastritis [51] To thispurpose we evaluate the tissue overexpression as a conse-quence of DNA hypomethylation of several oncoproteinsassociated with gastric cancer including STAT1 p73 FHITp16INK4a BRCA1 HSP90 and EGFRThese tissue biomark-ers were compared with H pylori and the OLGA stagingsystem As expected severe atrophy and OLGA stage IVwere the most relevant histological features of premalignantgastritis Among tissue biomarkers overexpression of p73was the most relevant finding Both data were integratedby systems pathology approach by performing SignificanceAnalysis of Microarrays [52 53] This approach shows thatp73 is stronger as a single variable when compared withOLGA stage IV (Figure 7)Therefore we believe that gastritis

Gastroenterology Research and Practice 7

with severe atrophy has a greater risk for developing gastriccancer if in addition overexpress p73 [51]

In summary the role of H pylori in the development ofchronic gastritis is not only associated to the bacteria itselfbut also to host and environmental factors Assessing risks forgastric cancer can be achieved by the evaluation of clinicalmorphological and molecular factors Among morphologi-cal criteria atrophy and intestinalmetaplasia can be evaluatedvia Sydney and OLGA approaches Molecular factors thatshould be considered are mostly E-cadherin methylationcirculating cell-free DNA of RPRMmethylation and overex-pression of p73 Finally a system pathology approach allowsintegrating all these factors that might be useful in switchingfrom an interpretive and subjectivemorphologically orientedapproach to a more objective evidence-based tissue markerapproach

Acknowledgment

This paper is supported by Grants nos FondefD09I1137 andFondecyt1111014 from the Government of Chile to A HCorvalan

References

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[2] M Kidd and I M Modlin ldquoA century of Helicobacter pyloriParadigms lostmdashparadigms regainedrdquo Digestion vol 59 no 1pp 1ndash15 1998

[3] R Schindler Gastritis William Heinmann London UK 1947[4] B J Marshall and J R Warren ldquoUnidentified curved bacilli in

the stomach of patients with gastritis and peptic ulcerationrdquoTheLancet vol 1 no 8390 pp 1311ndash1315 1984

[5] B C Jacobson JMCrawford and FA Farraye ldquoGI tract endo-scopic and tissue processing techniques and normal histologyin surgical pathology of the GI tractrdquo in Liver Biliary Tract andPancreas R D Odze and J R Goldblum Eds Elsevier 2009

[6] H M Malaty ldquoEpidemiology of Helicobacter pylori infectionrdquoBest Practice and Research vol 21 no 2 pp 205ndash214 2007

[7] T Shimizu T Akamatsu H Ota and T Katsuyama ldquoImmuno-histochemical detection of Helicobacter pylori in the surfacemucous gel layer and its clinicopathological significancerdquo Heli-cobacter vol 1 no 4 pp 197ndash206 1996

[8] F Carneiro E Fonseca and M Sobrinho-Simoes ldquoEpithelialdegeneration induced by Helicobacter pylorirdquo Human Pathol-ogy vol 23 no 11 pp 1314ndash1315 1992

[9] K M Leung P K Hui W Y Chan and T M M ThomasldquoHelicobacter pylori-related gastritis and gastric ulcer a contin-uum of progressive epithelial degenerationrdquo American Journalof Clinical Pathology vol 98 no 6 pp 569ndash574 1992

[10] R M Genta G M Lew and D Y Graham ldquoChanges in thegastric mucosa following eradication of Helicobacter pylorirdquoModern Pathology vol 6 no 3 pp 281ndash289 1993

[11] M F Dixon R M Genta J H Yardley and P Correa ldquoClassi-fication and grading of gastritis The updated Sydney systemInternational Workshop on the Histopathology of GastritisHouston 1994rdquoThe American Journal of Surgical Pathology vol20 no 10 pp 1161ndash1181 1996

[12] P Correa ldquoChronic gastritis a clinico-pathological classifica-tionrdquo American Journal of Gastroenterology vol 83 no 5 pp504ndash509 1988

[13] P Correa C Cuello E Duque et al ldquoGastric cancer in Colo-mbia III Natural history of precursor lesionsrdquo Journal of theNational Cancer Institute vol 57 no 5 pp 1027ndash1035 1976

[14] C Cuello P Correa W Haenszel et al ldquoGastric cancer inColombia I Cancer risk and suspect environmental agentsrdquoJournal of the National Cancer Institute vol 57 no 5 pp 1015ndash1020 1976

[15] W Haenszel P Correa C Cuello et al ldquoGastric cancer inColombia II Case control epidemiologic study of precursorlesionsrdquo Journal of the National Cancer Institute vol 57 no 5pp 1021ndash1026 1976

[16] P Correa W Haenszel C Cuello et al ldquoGastric precancerousprocess in a high risk population cohort follow-uprdquo CancerResearch vol 50 no 15 pp 4737ndash4740 1990

[17] H Ohata S Kitauchi N Yoshimura et al ldquoProgression ofchronic atrophic gastritis associated with Helicobacter pyloriinfection increases risk of gastric cancerrdquo International Journalof Cancer vol 109 no 1 pp 138ndash143 2004

[18] V Conteduca D Sansonno G Lauletta S Russi G Ingravalloand F Dammacco ldquoH pylori infection and gastric cancer stateof the art (Review)rdquo International Journal of Oncology vol 42no 1 pp 5ndash18 2013

[19] C A Gonzalez and A Agudo ldquoCarcinogenesis prevention andearly detection of gastric cancer where we are and where weshould gordquo International Journal of Cancer vol 130 no 4 pp745ndash753 2012

[20] P Correa and M B Piazuelo ldquoThe gastric precancerous cas-caderdquo Journal of Digestive Diseases vol 13 no 1 pp 2ndash9 2012

[21] R M Delahay and M Rugge ldquoPathogenesis of Helicobacterpylori infectionrdquo Helicobacter vol 17 supplement 1 pp 9ndash152012

[22] C A Gonzalez C Figueiredo C B Lic et al ldquoHelicobacterpylori cagA and vacA genotypes as predictors of progression ofgastric preneoplastic lesions a long-term follow-up in a high-risk area in Spainrdquo American Journal of Gastroenterology vol106 no 5 pp 867ndash874 2011

[23] E P Saraga D Gardiol and J Costa ldquoGastric dysplasia Ahistological follow-up studyrdquo American Journal of SurgicalPathology vol 11 no 10 pp 788ndash796 1987

[24] M J Coma del Corral F J Pardo-Mindan S Razquin and COjeda ldquoRisk of cancer in patients with gastric dysplasia follow-up study of 67 patientsrdquo Cancer vol 65 no 9 pp 2078ndash20851990

[25] H K Koch M Oehlert and W Oehlert ldquoAn evaluation ofgastric dysplasia in the years 1986 and 1987rdquo Pathology Researchand Practice vol 186 no 1 pp 80ndash84 1990

[26] J L Whiting A Sigurdsson D C Rowlands M T Hallisseyand J W L Fielding ldquoThe long term results of endoscopicsurveillance of premalignant gastric lesionsrdquo Gut vol 50 no3 pp 378ndash381 2002

[27] M Rugge M Cassaro F Di Mario et al ldquoThe long term out-come of gastric non-invasive neoplasiardquo Gut vol 52 no 8 pp1111ndash1116 2003

[28] KC R B RamesarD SA Sanders andDHopwood ldquoLimitedvalue of type III intestinalmetaplasia in predicting risk of gastriccarcinomardquo Journal of Clinical Pathology vol 40 no 11 pp1287ndash1290 1987

8 Gastroenterology Research and Practice

[29] S Silva M I Filipe and A Pinho ldquoVariants of intestinalmetaplasia in the evolution of chronic atrophic gastritis andgastric ulcer A follow up studyrdquo Gut vol 31 no 10 pp 1097ndash1104 1990

[30] T Rokkas M I Filipe and G E Sladen ldquoDetection of anincreased incidence of early gastric cancer in patients withintestinal metaplasia type III who are closely followed uprdquo Gutvol 32 no 10 pp 1110ndash1113 1991

[31] J M Conchillo G Houben A de Brune and R StockbruggerldquoIs type III intestinal metaplasia an obligatory precancerouslesion in intestinal-type gastric carcinomardquo European Journalof Cancer Prevention vol 10 no 4 pp 307ndash312 2001

[32] L Vannella E Lahner and B Annibale ldquoRisk for gastricneoplasias in patients with chronic atrophic gastritis a criticalreappraisalrdquo World Journal of Gastroenterology vol 18 no 12pp 1279ndash1285 2012

[33] M Rugge A Meggio G Pennelli et al ldquoGastritis staging inclinical practice the OLGA staging systemrdquo Gut vol 56 no 5pp 631ndash636 2007

[34] L G Capelle A C de Vries J Haringsma et al ldquoThe staging ofgastritis with the OLGA system by using intestinal metaplasiaas an accurate alternative for atrophic gastritisrdquoGastrointestinalEndoscopy vol 71 no 7 pp 1150ndash1158 2010

[35] M Rugge M de Boni G Pennelli et al ldquoGastritis OLGA-staging and gastric cancer risk a twelve-year clinico-patholog-ical follow-up studyrdquo Alimentary Pharmacology and Therapeu-tics vol 31 no 10 pp 1104ndash1111 2010

[36] M Rugge J G Kim V Mahachai et al ldquoOLGA gastritisstaging in young adults and country-specific gastric cancerriskrdquo International Journal of Surgical Pathology vol 16 no 2pp 150ndash154 2008

[37] G N Stemmermann ldquoIntestinal metaplasia of the stomach Astatus reportrdquo Cancer vol 74 no 2 pp 556ndash564 1994

[38] M Rugge M Fassan M Pizzi G Pennelli D Nitti and FFarinati ldquoOperative Link for Gastritis Assessment gastritisstaging incorporates intestinal metaplasia subtypingrdquo HumanPathology vol 42 no 10 pp 1539ndash1544 2011

[39] M Rugge P Correa M F Dixon et al ldquoGastric mucosal atro-phy interobserver consistency using new criteria for classifica-tion and gradingrdquo Alimentary Pharmacology and Therapeuticsvol 16 no 7 pp 1249ndash1259 2002

[40] W Yasui K Sentani N Sakamoto K Anami Y Naito andN Oue ldquoMolecular pathology of gastric cancer research andpracticerdquo Pathology Research and Practice vol 207 no 10 pp608ndash612 2011

[41] C O Gigek E S Chen D Q Calcagno F Wisnieski R RBurbano and M A Smith ldquoEpigenetic mechanisms in gastriccancerrdquo Epigenomics vol 4 no 3 pp 279ndash294 2012

[42] A H Corvalan and M J Maturana ldquoRecent patents of DNAmethylation biomarkers in gastrointestinal oncologyrdquo RecentPatents on DNA and Gene Sequences vol 4 no 3 pp 202ndash2092010

[43] C Zhao and X Bu ldquoPromoter methylation of tumor-relatedgenes in gastric carcinogenesisrdquo Histology and Histopathologyvol 27 no 10 pp 1271ndash1282 2012

[44] A O O Chan S K Lam B C YWong et al ldquoPromotermethy-lation of E-cadherin gene in gastric mucosa associated withHelicobacter pylori infection and in gastric cancerrdquoGut vol 52no 4 pp 502ndash506 2003

[45] A O O Chan and A Rashid ldquoCpG island methylation inprecursors of gastrointestinal malignanciesrdquo Current MolecularMedicine vol 6 no 4 pp 401ndash408 2006

[46] T Maekita K Nakazawa M Mihara et al ldquoHigh levels of aber-rant DNA methylation in Helicobacter pylori-infected gastricmucosae and its possible association with gastric cancer riskrdquoClinical Cancer Research vol 12 no 3 part 1 pp 989ndash995 2006

[47] R Ohki J Nemoto H Murasawa et al ldquoReprimo a new can-didate mediator of the p53-mediated cell cycle arrest at the G2phaserdquoThe Journal of Biological Chemistry vol 275 no 30 pp22627ndash22630 2000

[48] B G Schneider D F Peng M C Camargo et al ldquoPromoterDNAhypermethylation in gastric biopsies from subjects at highand low risk for gastric cancerrdquo International Journal of Cancervol 127 no 11 pp 2588ndash2597 2010

[49] C Bernal F Aguayo C Villarroel et al ldquoReprimo as a potentialbiomarker for early detection in gastric cancerrdquo Clinical CancerResearch vol 14 no 19 pp 6264ndash6269 2008

[50] N S Sapari M Loh A Vaithilingam and R Soong ldquoClinicalpotential of DNA methylation in gastric cancer a meta-analysisrdquo PLoS One vol 7 no 4 Article ID e36275 2012

[51] G Carrasco J Diaz J R Valbuena et al ldquoOverexpression ofp73 as a tissue marker for high-risk gastritisrdquo Clinical CancerResearch vol 16 no 12 pp 3253ndash3259 2010

[52] D Faratian ldquoSystems pathologyrdquo Breast Cancer Research vol12 supplement 4 article S4 2010

[53] A I Saeed N K Bhagabati J C Braisted et al ldquoTM4microar-ray software suiterdquoMethods in Enzymology vol 411 pp 134ndash1932006

Submit your manuscripts athttpwwwhindawicom

Stem CellsInternational

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

MEDIATORSINFLAMMATION

of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Behavioural Neurology

EndocrinologyInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Disease Markers

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

BioMed Research International

OncologyJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Oxidative Medicine and Cellular Longevity

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

PPAR Research

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Immunology ResearchHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Journal of

ObesityJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Computational and Mathematical Methods in Medicine

OphthalmologyJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Diabetes ResearchJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Research and TreatmentAIDS

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Gastroenterology Research and Practice

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Parkinsonrsquos Disease

Evidence-Based Complementary and Alternative Medicine

Volume 2014Hindawi Publishing Corporationhttpwwwhindawicom

2 Gastroenterology Research and Practice

(a) (b)

Figure 1 Normal gastric mucosa histology ((a) HampE 10x square 40x) Fundic glands are simple branched tubular glands that extend fromthe bottom of the gastric pits to themuscularis mucosae themore distinctive cells are parietal cells ((b) HampE 10x square 40x) Antral mucosais formed by branched coiled tubular glands lined by secretory cells similar in appearance to the surface mucus cells

orifice They are tubular somewhat tortuous andoccasionally branched and are mainly formed bymucus-secreting cells with occasional interspersedenteroendocrin cells

(2) Fundic glands are present throughout the entiregastric mucosa except for relative small regionsoccupied by cardiac and antral-pyloric glands Thefundic glands are simple branched tubular glandsthat extend from the bottom of the gastric pits tothemuscularis mucosae (Figure 1) and are formed byfour functional types of cells mucous neck cells chiefcells enteroendocrine cells parietal cells (also calledoxyntic cells) and undifferentiated cells

(3) Antral-pyloric glands are located in the pylori antrum(the part of the stomach between the fundus andthe pylorus)They are branched coiled tubular glandsand are lined by secretory cells similar in appearanceto the surface mucus cells (Figure 1) suggesting arelative viscous secretion Enteroendocrine cells arefound interspersed within the gland epithelium alongwith occasional parietal cells

The lamina propria is relatively scant and restricted to thelimited spaces surrounding the gastric pits and glands Thestroma is composed of reticular fibers with associated fibrob-lasts and smooth muscle cells It is also composed of lym-phocytes plasma cells macrophages and some eosinophilsThe lymphocytes are predominantly immunoglobulin (Ig)A-producing B cells IgG- and IgM-secreting cells are alsopresent Under normal conditions intraepithelial lympho-cytes are not present anywhere in the gastric mucosa Thereis also a small number of lamina propria T cells neutrophilsand mast cells The lamina propria also contains capillariesarterioles and nonmyelinated nerve fibers Small lymphoidaggregates usually located in close proximity to the muscu-laris mucosae at the base of the lamina propria especially atthe corpus could be present in normal gastric mucosa Incontrast the presence of lymphoid aggregates with germinalcenters is extremely rare in the mucosa of normal H pylorinegative adults [5]

3 Histopathology of Helicobacterpylori-Induced Chronic Gastritis

H pylori is a microaerophilic gram-negative bacteria Theearly phase of H pylori infection elicits an acute inflamma-tory response that is either asymptomatic or symptomaticwith short-lived clinical manifestations such as nausea andvomiting that evolve to a long-standing chronic gastritis [4]Its prevalence goes from less than 15 in some populationsto virtually 100 depending on socioeconomic status andcountry development [6] In industrialized countries (West-ern Europe United States Canada and Australia) exposuretends to occur later in life which results in a lower percentageof infected adults An average of 20 to 30 of adults isinfected by age 50 [6] and the prevalence ofH pylori infectionhas been steadily declining in emerging countries which isprobably a reflection of improved sanitary conditions as wellas the widespread use of antibiotics The foveolar epitheliumproduces a thick layer of mucus that plays a protective roleThis mucus layer is the primary site forH pylori colonization[7] so they characteristically attach to the surface mucouscells but do not penetrate them In chronic infection Hpylori contacts the surface epithelial membrane producingprominent epithelial degeneration [8 9] The cells oftenbecome irregular and cuboidal in shape showing a decreasein apical mucin content as well as occasional ldquodrop outsrdquowhich leaves small gaps in the epithelium and contributes toa ragged disorderly appearance

H pylori preferentially colonize the antrum but theymayinfect any part of the stomach where it causes gastritis Whentreated the bacteria migrate from the antrum to the corpusdecreasing the activity of antral gastritisMarked neutrophilicinfiltrates appear in the mucous neck region and laminapropria in early acute gastritis (Figure 2) when severe theyaggregate in the pit lumens to form pit abscesses Both theneutrophils and theH pylori destroy the epithelium causingthe mucous neck cells to proliferate in an effort to replacethe dying cells The regenerative pit bases are characterizedbymucin loss cytoplasmic basophilia increasedmitoses andhyperchromatic nuclei that are sometimes severe enough tomimic dysplasia

Gastroenterology Research and Practice 3

(a) (b)

Figure 2 Early acute superficial gastritis ((a) HampE 20x) Marked neutrophilic infiltrates appear in the mucous neck region and lamina witha pit micoabscess ((b) H pylori immunostaining rabbit polyclonal clone CH-20 429 Novocastra 40x) Numerous H pylori bacteria arepresent in the superficial foveolar epithelium

Neutrophilic inflammation and the presence of lymphoidfollicles with germinal centers are the two most distinctivehistological features ofH pylori infection and its eradicationcauses rapid neutrophil disappearance thus their continuedpresence is considered a valuable indicator of therapeuticfailureThe surface changes reverse rapidly and the epithelialcells acquire their normal shape and spatial organizationwithin a few days of H pylori eradication However anyatrophy that had developed remains as did the lymphoidaggregates [10] These features become permanent compo-nents of the once-infected gastric mucosa

4 Grading the Helicobacterpylori-Induced Chronic GastritisThe Updated Sydney System

The most widely used grading system for gastritis is theUpdated Sydney System [11] The system provides guidelinesfor generating systematic and uniform diagnostic reportsThe goal of the Sydney System is to make gastric biopsypathology reporting consistent so that clinical studies canbe performed and evaluated in a meaningful manner Thesystem classifies chronic gastritis on the basis of topographymorphology and when possible etiology into three broadcategories acute chronic and special (or distinctive) Thebiopsy protocol recommends that specimens from threecompartments (ie antrum incisura angularis and cor-pus) should be separately designated when submitted tothe pathology laboratory Each relevant pathologic feature(density of H pylori intensity of neutrophilic and mononu-clear inflammation atrophy of the antrum and corpus andintestinal metaplasia) should be graded on a standardizedvisual analogue scale (Figure 3) Each feature is assignedeither a numeric or descriptive value 0 for absent 1 formild 2 for moderate and 3 for marked (or severe) Thevalues of each specimen are then averaged separately for eachanatomic compartment (antrum and corpus) The next stepis to document the degree of inflammation in the two maingastric compartments (antrum and corpus) and to deter-mine whether the inflammation is similar in intensity (ie

pangastritis) or more severe in either the antrum (antrum-predominant gastritis) or the corpus (corpus-predominantgastritis)

5 Helicobacter pylori-InducedChronic Gastritis and Multistep Cascade ofGastric Carcinogenesis

In gastric cancer development H pylori-induced chronicgastritis is the first step of the so-called multistep cascadeof gastric cancer The cascade sequence of gastric carcino-genesis includes the nonatrophic chronic gastritis multifocalatrophic gastritis intestinal metaplasia low-grade dyspla-sia (low-grade noninvasive neoplasia) high-grade dysplasia(high-grade noninvasive neoplasia) and invasive adenocarci-noma as described by Correa as the ldquohuman model of gastriccarcinogenesisrdquo [12] This multistep model hypothesizes thatthe sequence of lesions reflects a dynamic process from anaıve inflammation caused by H pylori infection to a fullymalignant neoplasm of the stomach [13ndash16] Independentepidemiological studies have confirmed that these entitiesare all linked through a sequential cause-effect relationshipthus supporting the concept of a human model for gastriccarcinogenesis [17ndash19] In a recent review and update of thismodel it is also postulated that H pylori is present not onlyin the first step of gastric mucosa inflammation but as anetiological factor in every step of the precancerous cascade[20] In the first step H pylori infection targets normalmucosa withwell-preserved gastric glands by definition suchgastritis is nonatrophic At this point it can be cured byclearing H pylori infection or it may be evolving in twoways it can remain as nonatrophic or it progresses in severityleading to damage to the gastric glands whichmay eventuallydisappear [20] The progression depends on the interplay ofthree sets of etiological factors infectious agent hostrsquos geneticsusceptibility and external environment these determinethe susceptibility and severity of outcome in the subset ofindividuals that develop clinical disease [20 21]The presenceof virulent factors in the infecting H pylori strain is a knowndeterminant factor of the outcome of the infection Infection

4 Gastroenterology Research and Practice

Normal Mild Moderate Marked Normal Mild Moderate Marked

Atrophy antrum

Neutrophils

Mononuclear cells

Atrophy corpus

Intestinal metaplasia

H pylori

Figure 3 The Updated Sydney System visual standardized visual analogue scale Each feature is assigned either a numeric or descriptivevalue 0 for absent 1 for mild 2 for moderate and 3 for marked (or severe) Taken from Dixon et al [11]

Normal gastric mucosa

Non-atrophic gastritis

Non-atrophic gastritis

Duodenal ulcer

Multifocalatrophic gastritis

Intestinalmetaplasia

Dysplasia

Cancer

H pylori

cagAminus

vacA s2m2

cagA+

vacA s1m1

Figure 4 Multistep cascade of gastric cancer This sequence begins with the infection of H pylori to sequential steps of the precancerouscascades Taken from Correa and Piazuelo [20]

with cag-positive vacA s1m1 strains is associated with thedevelopment of gastric cancer while cag-negative vacA s2m2infection does not increase the risk of cancer and is associatedto the persistency of nonatrophic gastritis (Figure 4) [20 22]

6 Assessing Risks forGastric Cancer The Operative Link forGastritis Assessment (OLGA)

The risk ofmalignant transformation of the lesions associatedwith the multistep cascade of gastric cancer is poorly definedLong-term follow-up studies have shown a risk from 10 to17 in the case of dysplasia [23ndash27] For intestinalmetaplasiathe risk assessment has conflicting results and thereforea limited clinical value [28ndash32] The recently developedOperative Link for Gastritis Assessment (OLGA) stagingsystem [33] through the evaluation of the extension and

site of the atrophic changes is an attempt to evaluate therisk of chronic gastritis to progress to intestinal metaplasiaand gastric cancer [34ndash36] Long standingH pylori infectionmay lead to the loss of functional glands (atrophy) andreplacement of the normal gland and foveolar epitheliumby intestinal type cells (intestinal metaplasia) (Figure 5) thetwo main histological abnormalities invariable present as thebackground of gastric cancer [37] The extent and site ofthe atrophic changes significantly correlate with cancer risk[38] Two main types of atrophy can be recognized onecharacterized by the loss of glands accompanied by fibrosisor fibromuscular proliferation in the lamina propria andthe other characterized by the replacement of the normal(native) glands with metaplastic glands (ie glands that donot normally belong to that area) [39] The degree of atrophyand metaplasia can be assessed with OLGA staging systemfor atrophy risk assessment [33] This new system requiresthat specimens are taken according to the biopsy protocol

Gastroenterology Research and Practice 5

(a) (b)

Figure 5 Atrophy is the loss of appropriate glands ((a) HampE 10x) Antral gastric mucosa with accentuated atrophy because replacementby extensive intestinal metaplasia ((b) HampE 10x square 20x) Fundic-corporal gastric mucosa with extensive loss of gastric glands partiallyreplaced by pseudo-pyloric metaplasia

Table 1TheOLGA staging frame Atrophy is scored as the percentage of atrophic glands and scored on a four-tiered scale No atrophy (0) =score 0 mild atrophy (1ndash30) = score 1 moderate atrophy (31ndash60) = score 2 9 severe atrophy (gt60) = score 3These scores (0ndash3) are usedin the OLGA staging assessment in each 10 compartment Taken from Rugge et al Dig Liver Dis 2011 43S373-84 with permission of Elsevier

CorpusAtrophy score No atrophy Mild atrophy Moderate atrophy Severe atrophy

(score 0) (score 1) (score 2) (score 3)

Antrum

No atrophy (score 0)(including incisura angularis) Stage 0 Stage I Stage II Stage II

Mild atrophy (score 1)(including incisura angularis) Stage I Stage I Stage II Stage III

Moderate atrophy (score 2)(including incisura angularis) Stage II Stage II Stage III Stage IV

Severe atrophy (score 3)(including incisura angularis) Stage III Stage III Stage IV Stage IV

of the Sydney System and that atrophy is scored in a four-tiered scale (0ndash3) according to the visual analogue scale of theHouston-updated Sydney system The stage resulting fromthe combination of atrophic changes was assessed in the twomucosal compartments considered herein (Table 1)

7 Assessing Risks for Gastric CancerThe Epigenetic Bases of Chronic Gastritis

The molecular bases of the multistep process of gastriccarcinogenesis are highly relevant since it contributes greatlyto assess risks of gastric cancer Therefore chronic gastritisshould be understood as a disturbance in the balance betweentumor suppressor genes and oncogenes Many tumor sup-pressor genes have been identified in gastric cancer as wellas chronic gastritis [40] For example inactivation of p53tumor suppressor gene E-cadherin and DNA mismatchrepair genes (hMSH2 and hMLH1) responsible for loss ofheterozygosity (LOH) andmicrosatellite instability (MSI) arewell-recognized examples However multiple studies haveshown that mutation andor deletion is an infrequent mecha-nism of inactivating these well-established tumor suppressorgenes [41] In this scenario epigenetic alterations such as

DNA methylation have been proposed as an alternativemechanism for inactivation of tumor suppressor genes [41]DNA methylation is a process in which cytosines acquirea methyl group in 51015840 position only if they are followedby a guanine (CpG site) [42] Since DNA methylation hasbeen considered as an excellent candidate to explain howenvironmental factors may increase the risk of cancer ithas been proposed as a key element for the early events ofgastric carcinogenesis [43] For example Chan et al [44]found that DNA methylation of the promoter region of E-cadherin has been associated with H pylori infection Thisassociationwas independent of the age andor type of gastritis[44] Furthermore the same authors [45] also demonstratethat H pylori eradication with antibiotics reverses the DNAmethylation of E-cadherin (Figure 6) Similarly Maekita etal [46] analyzed the effect of H pylori infection on DNAmethylation for multiple genes (HAND1 HRASLS LOXp16 P41ARC and THBD) in H pylori negative and positivehealthy donors and gastric cancer patients Among healthydonors methylation levels were higher in H pylori positivesthan in H pylori negatives [46] Taken together these datasuggest that H pylori infection induces DNA methylationmostly in premalignant conditions rather than gastric canceritself [46] Among other tumor suppressor genes inactivated

6 Gastroenterology Research and Practice

Week 0Control Patient 1 Patient 2 Patient 3 Patient 4 Patient 5 Patient 6

MW U M U M U M U M U M U M U M

(a)

Week 0T ATGCGAGG TC GGG TGGGTGGGTCGTTAGTTT CG TTT T

(b)

Week 6Control Patient 1 Patient 2 Patient 3 Patient 4 Patient 5 Patient 6

MW U M U M U M U M U M U M U M

(c)

Week 6T GA TT G GT TGT GG T T GGT AGGT G AA TT T T TAG

(d)

Figure 6 CpG island methylation pattern at the E-cadherin gene in gastric mucosa from patients with dyspepsia (a) Before eradicationof H pylori (week 0) methylation was present in patients 3 5 and 6 (b) The methylated product was confirmed by sequencing using thesame methylated primer (c) After eradication of H pylori (week 6) methylation was not present in any patient (d) The methylated productwas again confirmed by sequencing using the same methylated primer No methylated cytosine was seen MW molecular weight marker Uunmethylated band M methylated band red color unmethylated cytosines converted to thymidine blue color methylated cytosines Takenfrom Chan and Rashid [45]

Controls NTAMs

p73

ATR-3IM-3CI-3OLGA stage-3OLGA stage-4

IM-0

ATR-0

CI-0

OLGA stage-0

Figure 7 Serial analysis formicroarray fromnontumor adjacentmucosa (NTAM) and chronic gastritis controls NTAMgroup is significantlycharacterized by the overexpression of p73 OLGA stages III to IV and severe atrophy (ATR-3) intestinal metaplasia (IM-3) and chronicinflammation (CI-3) according to the Sydney System Control group cases were significantly characterized by lack of intestinal metaplasia(IM-0) atrophy (ATR-0) and chronic inflammation (CI-0) False discovery rate = 0 Taken from Carrasco et al [51]

by DNAmethylation Reprimo (RPRM) a downstreammed-iator of p53-induced G2 cell cycle arrest [47] has beenrecently associated with more aggressive H pylori strains(cag-positive vacA s1m1 and EPIYA polymorphisms) inColombian residents from areas with high incidence ofgastric cancer [48] Furthermore we have identified thatDNA methylation of RPRM is not only found in gastricmucosa but also in the plasma of gastric cancer patients[49] Therefore this circulating cell-free DNA offers theopportunity for noninvasive assessing risks for gastric cancerSince a recent meta-analysis suggests that among severalcandidates circulating cell-free DNA of RPRM methylationis the most promising [50] this issue is currently underevaluation (Detection of Methylated Reprimo in Plasma forAsymptomatic Gastric Cancer DEMRAC study Finally we

have recently attempted to identify specific tissue biomarkersfor assessing the risk of premalignant gastritis [51] To thispurpose we evaluate the tissue overexpression as a conse-quence of DNA hypomethylation of several oncoproteinsassociated with gastric cancer including STAT1 p73 FHITp16INK4a BRCA1 HSP90 and EGFRThese tissue biomark-ers were compared with H pylori and the OLGA stagingsystem As expected severe atrophy and OLGA stage IVwere the most relevant histological features of premalignantgastritis Among tissue biomarkers overexpression of p73was the most relevant finding Both data were integratedby systems pathology approach by performing SignificanceAnalysis of Microarrays [52 53] This approach shows thatp73 is stronger as a single variable when compared withOLGA stage IV (Figure 7)Therefore we believe that gastritis

Gastroenterology Research and Practice 7

with severe atrophy has a greater risk for developing gastriccancer if in addition overexpress p73 [51]

In summary the role of H pylori in the development ofchronic gastritis is not only associated to the bacteria itselfbut also to host and environmental factors Assessing risks forgastric cancer can be achieved by the evaluation of clinicalmorphological and molecular factors Among morphologi-cal criteria atrophy and intestinalmetaplasia can be evaluatedvia Sydney and OLGA approaches Molecular factors thatshould be considered are mostly E-cadherin methylationcirculating cell-free DNA of RPRMmethylation and overex-pression of p73 Finally a system pathology approach allowsintegrating all these factors that might be useful in switchingfrom an interpretive and subjectivemorphologically orientedapproach to a more objective evidence-based tissue markerapproach

Acknowledgment

This paper is supported by Grants nos FondefD09I1137 andFondecyt1111014 from the Government of Chile to A HCorvalan

References

[1] N Figura and G Oderda ldquoReflections on the first descriptionof the presence of helicobacter species in the stomach ofmammalsrdquo Helicobacter vol 1 no 1 pp 4ndash5 1996

[2] M Kidd and I M Modlin ldquoA century of Helicobacter pyloriParadigms lostmdashparadigms regainedrdquo Digestion vol 59 no 1pp 1ndash15 1998

[3] R Schindler Gastritis William Heinmann London UK 1947[4] B J Marshall and J R Warren ldquoUnidentified curved bacilli in

the stomach of patients with gastritis and peptic ulcerationrdquoTheLancet vol 1 no 8390 pp 1311ndash1315 1984

[5] B C Jacobson JMCrawford and FA Farraye ldquoGI tract endo-scopic and tissue processing techniques and normal histologyin surgical pathology of the GI tractrdquo in Liver Biliary Tract andPancreas R D Odze and J R Goldblum Eds Elsevier 2009

[6] H M Malaty ldquoEpidemiology of Helicobacter pylori infectionrdquoBest Practice and Research vol 21 no 2 pp 205ndash214 2007

[7] T Shimizu T Akamatsu H Ota and T Katsuyama ldquoImmuno-histochemical detection of Helicobacter pylori in the surfacemucous gel layer and its clinicopathological significancerdquo Heli-cobacter vol 1 no 4 pp 197ndash206 1996

[8] F Carneiro E Fonseca and M Sobrinho-Simoes ldquoEpithelialdegeneration induced by Helicobacter pylorirdquo Human Pathol-ogy vol 23 no 11 pp 1314ndash1315 1992

[9] K M Leung P K Hui W Y Chan and T M M ThomasldquoHelicobacter pylori-related gastritis and gastric ulcer a contin-uum of progressive epithelial degenerationrdquo American Journalof Clinical Pathology vol 98 no 6 pp 569ndash574 1992

[10] R M Genta G M Lew and D Y Graham ldquoChanges in thegastric mucosa following eradication of Helicobacter pylorirdquoModern Pathology vol 6 no 3 pp 281ndash289 1993

[11] M F Dixon R M Genta J H Yardley and P Correa ldquoClassi-fication and grading of gastritis The updated Sydney systemInternational Workshop on the Histopathology of GastritisHouston 1994rdquoThe American Journal of Surgical Pathology vol20 no 10 pp 1161ndash1181 1996

[12] P Correa ldquoChronic gastritis a clinico-pathological classifica-tionrdquo American Journal of Gastroenterology vol 83 no 5 pp504ndash509 1988

[13] P Correa C Cuello E Duque et al ldquoGastric cancer in Colo-mbia III Natural history of precursor lesionsrdquo Journal of theNational Cancer Institute vol 57 no 5 pp 1027ndash1035 1976

[14] C Cuello P Correa W Haenszel et al ldquoGastric cancer inColombia I Cancer risk and suspect environmental agentsrdquoJournal of the National Cancer Institute vol 57 no 5 pp 1015ndash1020 1976

[15] W Haenszel P Correa C Cuello et al ldquoGastric cancer inColombia II Case control epidemiologic study of precursorlesionsrdquo Journal of the National Cancer Institute vol 57 no 5pp 1021ndash1026 1976

[16] P Correa W Haenszel C Cuello et al ldquoGastric precancerousprocess in a high risk population cohort follow-uprdquo CancerResearch vol 50 no 15 pp 4737ndash4740 1990

[17] H Ohata S Kitauchi N Yoshimura et al ldquoProgression ofchronic atrophic gastritis associated with Helicobacter pyloriinfection increases risk of gastric cancerrdquo International Journalof Cancer vol 109 no 1 pp 138ndash143 2004

[18] V Conteduca D Sansonno G Lauletta S Russi G Ingravalloand F Dammacco ldquoH pylori infection and gastric cancer stateof the art (Review)rdquo International Journal of Oncology vol 42no 1 pp 5ndash18 2013

[19] C A Gonzalez and A Agudo ldquoCarcinogenesis prevention andearly detection of gastric cancer where we are and where weshould gordquo International Journal of Cancer vol 130 no 4 pp745ndash753 2012

[20] P Correa and M B Piazuelo ldquoThe gastric precancerous cas-caderdquo Journal of Digestive Diseases vol 13 no 1 pp 2ndash9 2012

[21] R M Delahay and M Rugge ldquoPathogenesis of Helicobacterpylori infectionrdquo Helicobacter vol 17 supplement 1 pp 9ndash152012

[22] C A Gonzalez C Figueiredo C B Lic et al ldquoHelicobacterpylori cagA and vacA genotypes as predictors of progression ofgastric preneoplastic lesions a long-term follow-up in a high-risk area in Spainrdquo American Journal of Gastroenterology vol106 no 5 pp 867ndash874 2011

[23] E P Saraga D Gardiol and J Costa ldquoGastric dysplasia Ahistological follow-up studyrdquo American Journal of SurgicalPathology vol 11 no 10 pp 788ndash796 1987

[24] M J Coma del Corral F J Pardo-Mindan S Razquin and COjeda ldquoRisk of cancer in patients with gastric dysplasia follow-up study of 67 patientsrdquo Cancer vol 65 no 9 pp 2078ndash20851990

[25] H K Koch M Oehlert and W Oehlert ldquoAn evaluation ofgastric dysplasia in the years 1986 and 1987rdquo Pathology Researchand Practice vol 186 no 1 pp 80ndash84 1990

[26] J L Whiting A Sigurdsson D C Rowlands M T Hallisseyand J W L Fielding ldquoThe long term results of endoscopicsurveillance of premalignant gastric lesionsrdquo Gut vol 50 no3 pp 378ndash381 2002

[27] M Rugge M Cassaro F Di Mario et al ldquoThe long term out-come of gastric non-invasive neoplasiardquo Gut vol 52 no 8 pp1111ndash1116 2003

[28] KC R B RamesarD SA Sanders andDHopwood ldquoLimitedvalue of type III intestinalmetaplasia in predicting risk of gastriccarcinomardquo Journal of Clinical Pathology vol 40 no 11 pp1287ndash1290 1987

8 Gastroenterology Research and Practice

[29] S Silva M I Filipe and A Pinho ldquoVariants of intestinalmetaplasia in the evolution of chronic atrophic gastritis andgastric ulcer A follow up studyrdquo Gut vol 31 no 10 pp 1097ndash1104 1990

[30] T Rokkas M I Filipe and G E Sladen ldquoDetection of anincreased incidence of early gastric cancer in patients withintestinal metaplasia type III who are closely followed uprdquo Gutvol 32 no 10 pp 1110ndash1113 1991

[31] J M Conchillo G Houben A de Brune and R StockbruggerldquoIs type III intestinal metaplasia an obligatory precancerouslesion in intestinal-type gastric carcinomardquo European Journalof Cancer Prevention vol 10 no 4 pp 307ndash312 2001

[32] L Vannella E Lahner and B Annibale ldquoRisk for gastricneoplasias in patients with chronic atrophic gastritis a criticalreappraisalrdquo World Journal of Gastroenterology vol 18 no 12pp 1279ndash1285 2012

[33] M Rugge A Meggio G Pennelli et al ldquoGastritis staging inclinical practice the OLGA staging systemrdquo Gut vol 56 no 5pp 631ndash636 2007

[34] L G Capelle A C de Vries J Haringsma et al ldquoThe staging ofgastritis with the OLGA system by using intestinal metaplasiaas an accurate alternative for atrophic gastritisrdquoGastrointestinalEndoscopy vol 71 no 7 pp 1150ndash1158 2010

[35] M Rugge M de Boni G Pennelli et al ldquoGastritis OLGA-staging and gastric cancer risk a twelve-year clinico-patholog-ical follow-up studyrdquo Alimentary Pharmacology and Therapeu-tics vol 31 no 10 pp 1104ndash1111 2010

[36] M Rugge J G Kim V Mahachai et al ldquoOLGA gastritisstaging in young adults and country-specific gastric cancerriskrdquo International Journal of Surgical Pathology vol 16 no 2pp 150ndash154 2008

[37] G N Stemmermann ldquoIntestinal metaplasia of the stomach Astatus reportrdquo Cancer vol 74 no 2 pp 556ndash564 1994

[38] M Rugge M Fassan M Pizzi G Pennelli D Nitti and FFarinati ldquoOperative Link for Gastritis Assessment gastritisstaging incorporates intestinal metaplasia subtypingrdquo HumanPathology vol 42 no 10 pp 1539ndash1544 2011

[39] M Rugge P Correa M F Dixon et al ldquoGastric mucosal atro-phy interobserver consistency using new criteria for classifica-tion and gradingrdquo Alimentary Pharmacology and Therapeuticsvol 16 no 7 pp 1249ndash1259 2002

[40] W Yasui K Sentani N Sakamoto K Anami Y Naito andN Oue ldquoMolecular pathology of gastric cancer research andpracticerdquo Pathology Research and Practice vol 207 no 10 pp608ndash612 2011

[41] C O Gigek E S Chen D Q Calcagno F Wisnieski R RBurbano and M A Smith ldquoEpigenetic mechanisms in gastriccancerrdquo Epigenomics vol 4 no 3 pp 279ndash294 2012

[42] A H Corvalan and M J Maturana ldquoRecent patents of DNAmethylation biomarkers in gastrointestinal oncologyrdquo RecentPatents on DNA and Gene Sequences vol 4 no 3 pp 202ndash2092010

[43] C Zhao and X Bu ldquoPromoter methylation of tumor-relatedgenes in gastric carcinogenesisrdquo Histology and Histopathologyvol 27 no 10 pp 1271ndash1282 2012

[44] A O O Chan S K Lam B C YWong et al ldquoPromotermethy-lation of E-cadherin gene in gastric mucosa associated withHelicobacter pylori infection and in gastric cancerrdquoGut vol 52no 4 pp 502ndash506 2003

[45] A O O Chan and A Rashid ldquoCpG island methylation inprecursors of gastrointestinal malignanciesrdquo Current MolecularMedicine vol 6 no 4 pp 401ndash408 2006

[46] T Maekita K Nakazawa M Mihara et al ldquoHigh levels of aber-rant DNA methylation in Helicobacter pylori-infected gastricmucosae and its possible association with gastric cancer riskrdquoClinical Cancer Research vol 12 no 3 part 1 pp 989ndash995 2006

[47] R Ohki J Nemoto H Murasawa et al ldquoReprimo a new can-didate mediator of the p53-mediated cell cycle arrest at the G2phaserdquoThe Journal of Biological Chemistry vol 275 no 30 pp22627ndash22630 2000

[48] B G Schneider D F Peng M C Camargo et al ldquoPromoterDNAhypermethylation in gastric biopsies from subjects at highand low risk for gastric cancerrdquo International Journal of Cancervol 127 no 11 pp 2588ndash2597 2010

[49] C Bernal F Aguayo C Villarroel et al ldquoReprimo as a potentialbiomarker for early detection in gastric cancerrdquo Clinical CancerResearch vol 14 no 19 pp 6264ndash6269 2008

[50] N S Sapari M Loh A Vaithilingam and R Soong ldquoClinicalpotential of DNA methylation in gastric cancer a meta-analysisrdquo PLoS One vol 7 no 4 Article ID e36275 2012

[51] G Carrasco J Diaz J R Valbuena et al ldquoOverexpression ofp73 as a tissue marker for high-risk gastritisrdquo Clinical CancerResearch vol 16 no 12 pp 3253ndash3259 2010

[52] D Faratian ldquoSystems pathologyrdquo Breast Cancer Research vol12 supplement 4 article S4 2010

[53] A I Saeed N K Bhagabati J C Braisted et al ldquoTM4microar-ray software suiterdquoMethods in Enzymology vol 411 pp 134ndash1932006

Submit your manuscripts athttpwwwhindawicom

Stem CellsInternational

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

MEDIATORSINFLAMMATION

of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Behavioural Neurology

EndocrinologyInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Disease Markers

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

BioMed Research International

OncologyJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Oxidative Medicine and Cellular Longevity

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

PPAR Research

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Immunology ResearchHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Journal of

ObesityJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Computational and Mathematical Methods in Medicine

OphthalmologyJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Diabetes ResearchJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

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Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

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Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Parkinsonrsquos Disease

Evidence-Based Complementary and Alternative Medicine

Volume 2014Hindawi Publishing Corporationhttpwwwhindawicom

Gastroenterology Research and Practice 3

(a) (b)

Figure 2 Early acute superficial gastritis ((a) HampE 20x) Marked neutrophilic infiltrates appear in the mucous neck region and lamina witha pit micoabscess ((b) H pylori immunostaining rabbit polyclonal clone CH-20 429 Novocastra 40x) Numerous H pylori bacteria arepresent in the superficial foveolar epithelium

Neutrophilic inflammation and the presence of lymphoidfollicles with germinal centers are the two most distinctivehistological features ofH pylori infection and its eradicationcauses rapid neutrophil disappearance thus their continuedpresence is considered a valuable indicator of therapeuticfailureThe surface changes reverse rapidly and the epithelialcells acquire their normal shape and spatial organizationwithin a few days of H pylori eradication However anyatrophy that had developed remains as did the lymphoidaggregates [10] These features become permanent compo-nents of the once-infected gastric mucosa

4 Grading the Helicobacterpylori-Induced Chronic GastritisThe Updated Sydney System

The most widely used grading system for gastritis is theUpdated Sydney System [11] The system provides guidelinesfor generating systematic and uniform diagnostic reportsThe goal of the Sydney System is to make gastric biopsypathology reporting consistent so that clinical studies canbe performed and evaluated in a meaningful manner Thesystem classifies chronic gastritis on the basis of topographymorphology and when possible etiology into three broadcategories acute chronic and special (or distinctive) Thebiopsy protocol recommends that specimens from threecompartments (ie antrum incisura angularis and cor-pus) should be separately designated when submitted tothe pathology laboratory Each relevant pathologic feature(density of H pylori intensity of neutrophilic and mononu-clear inflammation atrophy of the antrum and corpus andintestinal metaplasia) should be graded on a standardizedvisual analogue scale (Figure 3) Each feature is assignedeither a numeric or descriptive value 0 for absent 1 formild 2 for moderate and 3 for marked (or severe) Thevalues of each specimen are then averaged separately for eachanatomic compartment (antrum and corpus) The next stepis to document the degree of inflammation in the two maingastric compartments (antrum and corpus) and to deter-mine whether the inflammation is similar in intensity (ie

pangastritis) or more severe in either the antrum (antrum-predominant gastritis) or the corpus (corpus-predominantgastritis)

5 Helicobacter pylori-InducedChronic Gastritis and Multistep Cascade ofGastric Carcinogenesis

In gastric cancer development H pylori-induced chronicgastritis is the first step of the so-called multistep cascadeof gastric cancer The cascade sequence of gastric carcino-genesis includes the nonatrophic chronic gastritis multifocalatrophic gastritis intestinal metaplasia low-grade dyspla-sia (low-grade noninvasive neoplasia) high-grade dysplasia(high-grade noninvasive neoplasia) and invasive adenocarci-noma as described by Correa as the ldquohuman model of gastriccarcinogenesisrdquo [12] This multistep model hypothesizes thatthe sequence of lesions reflects a dynamic process from anaıve inflammation caused by H pylori infection to a fullymalignant neoplasm of the stomach [13ndash16] Independentepidemiological studies have confirmed that these entitiesare all linked through a sequential cause-effect relationshipthus supporting the concept of a human model for gastriccarcinogenesis [17ndash19] In a recent review and update of thismodel it is also postulated that H pylori is present not onlyin the first step of gastric mucosa inflammation but as anetiological factor in every step of the precancerous cascade[20] In the first step H pylori infection targets normalmucosa withwell-preserved gastric glands by definition suchgastritis is nonatrophic At this point it can be cured byclearing H pylori infection or it may be evolving in twoways it can remain as nonatrophic or it progresses in severityleading to damage to the gastric glands whichmay eventuallydisappear [20] The progression depends on the interplay ofthree sets of etiological factors infectious agent hostrsquos geneticsusceptibility and external environment these determinethe susceptibility and severity of outcome in the subset ofindividuals that develop clinical disease [20 21]The presenceof virulent factors in the infecting H pylori strain is a knowndeterminant factor of the outcome of the infection Infection

4 Gastroenterology Research and Practice

Normal Mild Moderate Marked Normal Mild Moderate Marked

Atrophy antrum

Neutrophils

Mononuclear cells

Atrophy corpus

Intestinal metaplasia

H pylori

Figure 3 The Updated Sydney System visual standardized visual analogue scale Each feature is assigned either a numeric or descriptivevalue 0 for absent 1 for mild 2 for moderate and 3 for marked (or severe) Taken from Dixon et al [11]

Normal gastric mucosa

Non-atrophic gastritis

Non-atrophic gastritis

Duodenal ulcer

Multifocalatrophic gastritis

Intestinalmetaplasia

Dysplasia

Cancer

H pylori

cagAminus

vacA s2m2

cagA+

vacA s1m1

Figure 4 Multistep cascade of gastric cancer This sequence begins with the infection of H pylori to sequential steps of the precancerouscascades Taken from Correa and Piazuelo [20]

with cag-positive vacA s1m1 strains is associated with thedevelopment of gastric cancer while cag-negative vacA s2m2infection does not increase the risk of cancer and is associatedto the persistency of nonatrophic gastritis (Figure 4) [20 22]

6 Assessing Risks forGastric Cancer The Operative Link forGastritis Assessment (OLGA)

The risk ofmalignant transformation of the lesions associatedwith the multistep cascade of gastric cancer is poorly definedLong-term follow-up studies have shown a risk from 10 to17 in the case of dysplasia [23ndash27] For intestinalmetaplasiathe risk assessment has conflicting results and thereforea limited clinical value [28ndash32] The recently developedOperative Link for Gastritis Assessment (OLGA) stagingsystem [33] through the evaluation of the extension and

site of the atrophic changes is an attempt to evaluate therisk of chronic gastritis to progress to intestinal metaplasiaand gastric cancer [34ndash36] Long standingH pylori infectionmay lead to the loss of functional glands (atrophy) andreplacement of the normal gland and foveolar epitheliumby intestinal type cells (intestinal metaplasia) (Figure 5) thetwo main histological abnormalities invariable present as thebackground of gastric cancer [37] The extent and site ofthe atrophic changes significantly correlate with cancer risk[38] Two main types of atrophy can be recognized onecharacterized by the loss of glands accompanied by fibrosisor fibromuscular proliferation in the lamina propria andthe other characterized by the replacement of the normal(native) glands with metaplastic glands (ie glands that donot normally belong to that area) [39] The degree of atrophyand metaplasia can be assessed with OLGA staging systemfor atrophy risk assessment [33] This new system requiresthat specimens are taken according to the biopsy protocol

Gastroenterology Research and Practice 5

(a) (b)

Figure 5 Atrophy is the loss of appropriate glands ((a) HampE 10x) Antral gastric mucosa with accentuated atrophy because replacementby extensive intestinal metaplasia ((b) HampE 10x square 20x) Fundic-corporal gastric mucosa with extensive loss of gastric glands partiallyreplaced by pseudo-pyloric metaplasia

Table 1TheOLGA staging frame Atrophy is scored as the percentage of atrophic glands and scored on a four-tiered scale No atrophy (0) =score 0 mild atrophy (1ndash30) = score 1 moderate atrophy (31ndash60) = score 2 9 severe atrophy (gt60) = score 3These scores (0ndash3) are usedin the OLGA staging assessment in each 10 compartment Taken from Rugge et al Dig Liver Dis 2011 43S373-84 with permission of Elsevier

CorpusAtrophy score No atrophy Mild atrophy Moderate atrophy Severe atrophy

(score 0) (score 1) (score 2) (score 3)

Antrum

No atrophy (score 0)(including incisura angularis) Stage 0 Stage I Stage II Stage II

Mild atrophy (score 1)(including incisura angularis) Stage I Stage I Stage II Stage III

Moderate atrophy (score 2)(including incisura angularis) Stage II Stage II Stage III Stage IV

Severe atrophy (score 3)(including incisura angularis) Stage III Stage III Stage IV Stage IV

of the Sydney System and that atrophy is scored in a four-tiered scale (0ndash3) according to the visual analogue scale of theHouston-updated Sydney system The stage resulting fromthe combination of atrophic changes was assessed in the twomucosal compartments considered herein (Table 1)

7 Assessing Risks for Gastric CancerThe Epigenetic Bases of Chronic Gastritis

The molecular bases of the multistep process of gastriccarcinogenesis are highly relevant since it contributes greatlyto assess risks of gastric cancer Therefore chronic gastritisshould be understood as a disturbance in the balance betweentumor suppressor genes and oncogenes Many tumor sup-pressor genes have been identified in gastric cancer as wellas chronic gastritis [40] For example inactivation of p53tumor suppressor gene E-cadherin and DNA mismatchrepair genes (hMSH2 and hMLH1) responsible for loss ofheterozygosity (LOH) andmicrosatellite instability (MSI) arewell-recognized examples However multiple studies haveshown that mutation andor deletion is an infrequent mecha-nism of inactivating these well-established tumor suppressorgenes [41] In this scenario epigenetic alterations such as

DNA methylation have been proposed as an alternativemechanism for inactivation of tumor suppressor genes [41]DNA methylation is a process in which cytosines acquirea methyl group in 51015840 position only if they are followedby a guanine (CpG site) [42] Since DNA methylation hasbeen considered as an excellent candidate to explain howenvironmental factors may increase the risk of cancer ithas been proposed as a key element for the early events ofgastric carcinogenesis [43] For example Chan et al [44]found that DNA methylation of the promoter region of E-cadherin has been associated with H pylori infection Thisassociationwas independent of the age andor type of gastritis[44] Furthermore the same authors [45] also demonstratethat H pylori eradication with antibiotics reverses the DNAmethylation of E-cadherin (Figure 6) Similarly Maekita etal [46] analyzed the effect of H pylori infection on DNAmethylation for multiple genes (HAND1 HRASLS LOXp16 P41ARC and THBD) in H pylori negative and positivehealthy donors and gastric cancer patients Among healthydonors methylation levels were higher in H pylori positivesthan in H pylori negatives [46] Taken together these datasuggest that H pylori infection induces DNA methylationmostly in premalignant conditions rather than gastric canceritself [46] Among other tumor suppressor genes inactivated

6 Gastroenterology Research and Practice

Week 0Control Patient 1 Patient 2 Patient 3 Patient 4 Patient 5 Patient 6

MW U M U M U M U M U M U M U M

(a)

Week 0T ATGCGAGG TC GGG TGGGTGGGTCGTTAGTTT CG TTT T

(b)

Week 6Control Patient 1 Patient 2 Patient 3 Patient 4 Patient 5 Patient 6

MW U M U M U M U M U M U M U M

(c)

Week 6T GA TT G GT TGT GG T T GGT AGGT G AA TT T T TAG

(d)

Figure 6 CpG island methylation pattern at the E-cadherin gene in gastric mucosa from patients with dyspepsia (a) Before eradicationof H pylori (week 0) methylation was present in patients 3 5 and 6 (b) The methylated product was confirmed by sequencing using thesame methylated primer (c) After eradication of H pylori (week 6) methylation was not present in any patient (d) The methylated productwas again confirmed by sequencing using the same methylated primer No methylated cytosine was seen MW molecular weight marker Uunmethylated band M methylated band red color unmethylated cytosines converted to thymidine blue color methylated cytosines Takenfrom Chan and Rashid [45]

Controls NTAMs

p73

ATR-3IM-3CI-3OLGA stage-3OLGA stage-4

IM-0

ATR-0

CI-0

OLGA stage-0

Figure 7 Serial analysis formicroarray fromnontumor adjacentmucosa (NTAM) and chronic gastritis controls NTAMgroup is significantlycharacterized by the overexpression of p73 OLGA stages III to IV and severe atrophy (ATR-3) intestinal metaplasia (IM-3) and chronicinflammation (CI-3) according to the Sydney System Control group cases were significantly characterized by lack of intestinal metaplasia(IM-0) atrophy (ATR-0) and chronic inflammation (CI-0) False discovery rate = 0 Taken from Carrasco et al [51]

by DNAmethylation Reprimo (RPRM) a downstreammed-iator of p53-induced G2 cell cycle arrest [47] has beenrecently associated with more aggressive H pylori strains(cag-positive vacA s1m1 and EPIYA polymorphisms) inColombian residents from areas with high incidence ofgastric cancer [48] Furthermore we have identified thatDNA methylation of RPRM is not only found in gastricmucosa but also in the plasma of gastric cancer patients[49] Therefore this circulating cell-free DNA offers theopportunity for noninvasive assessing risks for gastric cancerSince a recent meta-analysis suggests that among severalcandidates circulating cell-free DNA of RPRM methylationis the most promising [50] this issue is currently underevaluation (Detection of Methylated Reprimo in Plasma forAsymptomatic Gastric Cancer DEMRAC study Finally we

have recently attempted to identify specific tissue biomarkersfor assessing the risk of premalignant gastritis [51] To thispurpose we evaluate the tissue overexpression as a conse-quence of DNA hypomethylation of several oncoproteinsassociated with gastric cancer including STAT1 p73 FHITp16INK4a BRCA1 HSP90 and EGFRThese tissue biomark-ers were compared with H pylori and the OLGA stagingsystem As expected severe atrophy and OLGA stage IVwere the most relevant histological features of premalignantgastritis Among tissue biomarkers overexpression of p73was the most relevant finding Both data were integratedby systems pathology approach by performing SignificanceAnalysis of Microarrays [52 53] This approach shows thatp73 is stronger as a single variable when compared withOLGA stage IV (Figure 7)Therefore we believe that gastritis

Gastroenterology Research and Practice 7

with severe atrophy has a greater risk for developing gastriccancer if in addition overexpress p73 [51]

In summary the role of H pylori in the development ofchronic gastritis is not only associated to the bacteria itselfbut also to host and environmental factors Assessing risks forgastric cancer can be achieved by the evaluation of clinicalmorphological and molecular factors Among morphologi-cal criteria atrophy and intestinalmetaplasia can be evaluatedvia Sydney and OLGA approaches Molecular factors thatshould be considered are mostly E-cadherin methylationcirculating cell-free DNA of RPRMmethylation and overex-pression of p73 Finally a system pathology approach allowsintegrating all these factors that might be useful in switchingfrom an interpretive and subjectivemorphologically orientedapproach to a more objective evidence-based tissue markerapproach

Acknowledgment

This paper is supported by Grants nos FondefD09I1137 andFondecyt1111014 from the Government of Chile to A HCorvalan

References

[1] N Figura and G Oderda ldquoReflections on the first descriptionof the presence of helicobacter species in the stomach ofmammalsrdquo Helicobacter vol 1 no 1 pp 4ndash5 1996

[2] M Kidd and I M Modlin ldquoA century of Helicobacter pyloriParadigms lostmdashparadigms regainedrdquo Digestion vol 59 no 1pp 1ndash15 1998

[3] R Schindler Gastritis William Heinmann London UK 1947[4] B J Marshall and J R Warren ldquoUnidentified curved bacilli in

the stomach of patients with gastritis and peptic ulcerationrdquoTheLancet vol 1 no 8390 pp 1311ndash1315 1984

[5] B C Jacobson JMCrawford and FA Farraye ldquoGI tract endo-scopic and tissue processing techniques and normal histologyin surgical pathology of the GI tractrdquo in Liver Biliary Tract andPancreas R D Odze and J R Goldblum Eds Elsevier 2009

[6] H M Malaty ldquoEpidemiology of Helicobacter pylori infectionrdquoBest Practice and Research vol 21 no 2 pp 205ndash214 2007

[7] T Shimizu T Akamatsu H Ota and T Katsuyama ldquoImmuno-histochemical detection of Helicobacter pylori in the surfacemucous gel layer and its clinicopathological significancerdquo Heli-cobacter vol 1 no 4 pp 197ndash206 1996

[8] F Carneiro E Fonseca and M Sobrinho-Simoes ldquoEpithelialdegeneration induced by Helicobacter pylorirdquo Human Pathol-ogy vol 23 no 11 pp 1314ndash1315 1992

[9] K M Leung P K Hui W Y Chan and T M M ThomasldquoHelicobacter pylori-related gastritis and gastric ulcer a contin-uum of progressive epithelial degenerationrdquo American Journalof Clinical Pathology vol 98 no 6 pp 569ndash574 1992

[10] R M Genta G M Lew and D Y Graham ldquoChanges in thegastric mucosa following eradication of Helicobacter pylorirdquoModern Pathology vol 6 no 3 pp 281ndash289 1993

[11] M F Dixon R M Genta J H Yardley and P Correa ldquoClassi-fication and grading of gastritis The updated Sydney systemInternational Workshop on the Histopathology of GastritisHouston 1994rdquoThe American Journal of Surgical Pathology vol20 no 10 pp 1161ndash1181 1996

[12] P Correa ldquoChronic gastritis a clinico-pathological classifica-tionrdquo American Journal of Gastroenterology vol 83 no 5 pp504ndash509 1988

[13] P Correa C Cuello E Duque et al ldquoGastric cancer in Colo-mbia III Natural history of precursor lesionsrdquo Journal of theNational Cancer Institute vol 57 no 5 pp 1027ndash1035 1976

[14] C Cuello P Correa W Haenszel et al ldquoGastric cancer inColombia I Cancer risk and suspect environmental agentsrdquoJournal of the National Cancer Institute vol 57 no 5 pp 1015ndash1020 1976

[15] W Haenszel P Correa C Cuello et al ldquoGastric cancer inColombia II Case control epidemiologic study of precursorlesionsrdquo Journal of the National Cancer Institute vol 57 no 5pp 1021ndash1026 1976

[16] P Correa W Haenszel C Cuello et al ldquoGastric precancerousprocess in a high risk population cohort follow-uprdquo CancerResearch vol 50 no 15 pp 4737ndash4740 1990

[17] H Ohata S Kitauchi N Yoshimura et al ldquoProgression ofchronic atrophic gastritis associated with Helicobacter pyloriinfection increases risk of gastric cancerrdquo International Journalof Cancer vol 109 no 1 pp 138ndash143 2004

[18] V Conteduca D Sansonno G Lauletta S Russi G Ingravalloand F Dammacco ldquoH pylori infection and gastric cancer stateof the art (Review)rdquo International Journal of Oncology vol 42no 1 pp 5ndash18 2013

[19] C A Gonzalez and A Agudo ldquoCarcinogenesis prevention andearly detection of gastric cancer where we are and where weshould gordquo International Journal of Cancer vol 130 no 4 pp745ndash753 2012

[20] P Correa and M B Piazuelo ldquoThe gastric precancerous cas-caderdquo Journal of Digestive Diseases vol 13 no 1 pp 2ndash9 2012

[21] R M Delahay and M Rugge ldquoPathogenesis of Helicobacterpylori infectionrdquo Helicobacter vol 17 supplement 1 pp 9ndash152012

[22] C A Gonzalez C Figueiredo C B Lic et al ldquoHelicobacterpylori cagA and vacA genotypes as predictors of progression ofgastric preneoplastic lesions a long-term follow-up in a high-risk area in Spainrdquo American Journal of Gastroenterology vol106 no 5 pp 867ndash874 2011

[23] E P Saraga D Gardiol and J Costa ldquoGastric dysplasia Ahistological follow-up studyrdquo American Journal of SurgicalPathology vol 11 no 10 pp 788ndash796 1987

[24] M J Coma del Corral F J Pardo-Mindan S Razquin and COjeda ldquoRisk of cancer in patients with gastric dysplasia follow-up study of 67 patientsrdquo Cancer vol 65 no 9 pp 2078ndash20851990

[25] H K Koch M Oehlert and W Oehlert ldquoAn evaluation ofgastric dysplasia in the years 1986 and 1987rdquo Pathology Researchand Practice vol 186 no 1 pp 80ndash84 1990

[26] J L Whiting A Sigurdsson D C Rowlands M T Hallisseyand J W L Fielding ldquoThe long term results of endoscopicsurveillance of premalignant gastric lesionsrdquo Gut vol 50 no3 pp 378ndash381 2002

[27] M Rugge M Cassaro F Di Mario et al ldquoThe long term out-come of gastric non-invasive neoplasiardquo Gut vol 52 no 8 pp1111ndash1116 2003

[28] KC R B RamesarD SA Sanders andDHopwood ldquoLimitedvalue of type III intestinalmetaplasia in predicting risk of gastriccarcinomardquo Journal of Clinical Pathology vol 40 no 11 pp1287ndash1290 1987

8 Gastroenterology Research and Practice

[29] S Silva M I Filipe and A Pinho ldquoVariants of intestinalmetaplasia in the evolution of chronic atrophic gastritis andgastric ulcer A follow up studyrdquo Gut vol 31 no 10 pp 1097ndash1104 1990

[30] T Rokkas M I Filipe and G E Sladen ldquoDetection of anincreased incidence of early gastric cancer in patients withintestinal metaplasia type III who are closely followed uprdquo Gutvol 32 no 10 pp 1110ndash1113 1991

[31] J M Conchillo G Houben A de Brune and R StockbruggerldquoIs type III intestinal metaplasia an obligatory precancerouslesion in intestinal-type gastric carcinomardquo European Journalof Cancer Prevention vol 10 no 4 pp 307ndash312 2001

[32] L Vannella E Lahner and B Annibale ldquoRisk for gastricneoplasias in patients with chronic atrophic gastritis a criticalreappraisalrdquo World Journal of Gastroenterology vol 18 no 12pp 1279ndash1285 2012

[33] M Rugge A Meggio G Pennelli et al ldquoGastritis staging inclinical practice the OLGA staging systemrdquo Gut vol 56 no 5pp 631ndash636 2007

[34] L G Capelle A C de Vries J Haringsma et al ldquoThe staging ofgastritis with the OLGA system by using intestinal metaplasiaas an accurate alternative for atrophic gastritisrdquoGastrointestinalEndoscopy vol 71 no 7 pp 1150ndash1158 2010

[35] M Rugge M de Boni G Pennelli et al ldquoGastritis OLGA-staging and gastric cancer risk a twelve-year clinico-patholog-ical follow-up studyrdquo Alimentary Pharmacology and Therapeu-tics vol 31 no 10 pp 1104ndash1111 2010

[36] M Rugge J G Kim V Mahachai et al ldquoOLGA gastritisstaging in young adults and country-specific gastric cancerriskrdquo International Journal of Surgical Pathology vol 16 no 2pp 150ndash154 2008

[37] G N Stemmermann ldquoIntestinal metaplasia of the stomach Astatus reportrdquo Cancer vol 74 no 2 pp 556ndash564 1994

[38] M Rugge M Fassan M Pizzi G Pennelli D Nitti and FFarinati ldquoOperative Link for Gastritis Assessment gastritisstaging incorporates intestinal metaplasia subtypingrdquo HumanPathology vol 42 no 10 pp 1539ndash1544 2011

[39] M Rugge P Correa M F Dixon et al ldquoGastric mucosal atro-phy interobserver consistency using new criteria for classifica-tion and gradingrdquo Alimentary Pharmacology and Therapeuticsvol 16 no 7 pp 1249ndash1259 2002

[40] W Yasui K Sentani N Sakamoto K Anami Y Naito andN Oue ldquoMolecular pathology of gastric cancer research andpracticerdquo Pathology Research and Practice vol 207 no 10 pp608ndash612 2011

[41] C O Gigek E S Chen D Q Calcagno F Wisnieski R RBurbano and M A Smith ldquoEpigenetic mechanisms in gastriccancerrdquo Epigenomics vol 4 no 3 pp 279ndash294 2012

[42] A H Corvalan and M J Maturana ldquoRecent patents of DNAmethylation biomarkers in gastrointestinal oncologyrdquo RecentPatents on DNA and Gene Sequences vol 4 no 3 pp 202ndash2092010

[43] C Zhao and X Bu ldquoPromoter methylation of tumor-relatedgenes in gastric carcinogenesisrdquo Histology and Histopathologyvol 27 no 10 pp 1271ndash1282 2012

[44] A O O Chan S K Lam B C YWong et al ldquoPromotermethy-lation of E-cadherin gene in gastric mucosa associated withHelicobacter pylori infection and in gastric cancerrdquoGut vol 52no 4 pp 502ndash506 2003

[45] A O O Chan and A Rashid ldquoCpG island methylation inprecursors of gastrointestinal malignanciesrdquo Current MolecularMedicine vol 6 no 4 pp 401ndash408 2006

[46] T Maekita K Nakazawa M Mihara et al ldquoHigh levels of aber-rant DNA methylation in Helicobacter pylori-infected gastricmucosae and its possible association with gastric cancer riskrdquoClinical Cancer Research vol 12 no 3 part 1 pp 989ndash995 2006

[47] R Ohki J Nemoto H Murasawa et al ldquoReprimo a new can-didate mediator of the p53-mediated cell cycle arrest at the G2phaserdquoThe Journal of Biological Chemistry vol 275 no 30 pp22627ndash22630 2000

[48] B G Schneider D F Peng M C Camargo et al ldquoPromoterDNAhypermethylation in gastric biopsies from subjects at highand low risk for gastric cancerrdquo International Journal of Cancervol 127 no 11 pp 2588ndash2597 2010

[49] C Bernal F Aguayo C Villarroel et al ldquoReprimo as a potentialbiomarker for early detection in gastric cancerrdquo Clinical CancerResearch vol 14 no 19 pp 6264ndash6269 2008

[50] N S Sapari M Loh A Vaithilingam and R Soong ldquoClinicalpotential of DNA methylation in gastric cancer a meta-analysisrdquo PLoS One vol 7 no 4 Article ID e36275 2012

[51] G Carrasco J Diaz J R Valbuena et al ldquoOverexpression ofp73 as a tissue marker for high-risk gastritisrdquo Clinical CancerResearch vol 16 no 12 pp 3253ndash3259 2010

[52] D Faratian ldquoSystems pathologyrdquo Breast Cancer Research vol12 supplement 4 article S4 2010

[53] A I Saeed N K Bhagabati J C Braisted et al ldquoTM4microar-ray software suiterdquoMethods in Enzymology vol 411 pp 134ndash1932006

Submit your manuscripts athttpwwwhindawicom

Stem CellsInternational

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

MEDIATORSINFLAMMATION

of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Behavioural Neurology

EndocrinologyInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Disease Markers

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

BioMed Research International

OncologyJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Oxidative Medicine and Cellular Longevity

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

PPAR Research

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Immunology ResearchHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Journal of

ObesityJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Computational and Mathematical Methods in Medicine

OphthalmologyJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Diabetes ResearchJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Research and TreatmentAIDS

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Gastroenterology Research and Practice

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Parkinsonrsquos Disease

Evidence-Based Complementary and Alternative Medicine

Volume 2014Hindawi Publishing Corporationhttpwwwhindawicom

4 Gastroenterology Research and Practice

Normal Mild Moderate Marked Normal Mild Moderate Marked

Atrophy antrum

Neutrophils

Mononuclear cells

Atrophy corpus

Intestinal metaplasia

H pylori

Figure 3 The Updated Sydney System visual standardized visual analogue scale Each feature is assigned either a numeric or descriptivevalue 0 for absent 1 for mild 2 for moderate and 3 for marked (or severe) Taken from Dixon et al [11]

Normal gastric mucosa

Non-atrophic gastritis

Non-atrophic gastritis

Duodenal ulcer

Multifocalatrophic gastritis

Intestinalmetaplasia

Dysplasia

Cancer

H pylori

cagAminus

vacA s2m2

cagA+

vacA s1m1

Figure 4 Multistep cascade of gastric cancer This sequence begins with the infection of H pylori to sequential steps of the precancerouscascades Taken from Correa and Piazuelo [20]

with cag-positive vacA s1m1 strains is associated with thedevelopment of gastric cancer while cag-negative vacA s2m2infection does not increase the risk of cancer and is associatedto the persistency of nonatrophic gastritis (Figure 4) [20 22]

6 Assessing Risks forGastric Cancer The Operative Link forGastritis Assessment (OLGA)

The risk ofmalignant transformation of the lesions associatedwith the multistep cascade of gastric cancer is poorly definedLong-term follow-up studies have shown a risk from 10 to17 in the case of dysplasia [23ndash27] For intestinalmetaplasiathe risk assessment has conflicting results and thereforea limited clinical value [28ndash32] The recently developedOperative Link for Gastritis Assessment (OLGA) stagingsystem [33] through the evaluation of the extension and

site of the atrophic changes is an attempt to evaluate therisk of chronic gastritis to progress to intestinal metaplasiaand gastric cancer [34ndash36] Long standingH pylori infectionmay lead to the loss of functional glands (atrophy) andreplacement of the normal gland and foveolar epitheliumby intestinal type cells (intestinal metaplasia) (Figure 5) thetwo main histological abnormalities invariable present as thebackground of gastric cancer [37] The extent and site ofthe atrophic changes significantly correlate with cancer risk[38] Two main types of atrophy can be recognized onecharacterized by the loss of glands accompanied by fibrosisor fibromuscular proliferation in the lamina propria andthe other characterized by the replacement of the normal(native) glands with metaplastic glands (ie glands that donot normally belong to that area) [39] The degree of atrophyand metaplasia can be assessed with OLGA staging systemfor atrophy risk assessment [33] This new system requiresthat specimens are taken according to the biopsy protocol

Gastroenterology Research and Practice 5

(a) (b)

Figure 5 Atrophy is the loss of appropriate glands ((a) HampE 10x) Antral gastric mucosa with accentuated atrophy because replacementby extensive intestinal metaplasia ((b) HampE 10x square 20x) Fundic-corporal gastric mucosa with extensive loss of gastric glands partiallyreplaced by pseudo-pyloric metaplasia

Table 1TheOLGA staging frame Atrophy is scored as the percentage of atrophic glands and scored on a four-tiered scale No atrophy (0) =score 0 mild atrophy (1ndash30) = score 1 moderate atrophy (31ndash60) = score 2 9 severe atrophy (gt60) = score 3These scores (0ndash3) are usedin the OLGA staging assessment in each 10 compartment Taken from Rugge et al Dig Liver Dis 2011 43S373-84 with permission of Elsevier

CorpusAtrophy score No atrophy Mild atrophy Moderate atrophy Severe atrophy

(score 0) (score 1) (score 2) (score 3)

Antrum

No atrophy (score 0)(including incisura angularis) Stage 0 Stage I Stage II Stage II

Mild atrophy (score 1)(including incisura angularis) Stage I Stage I Stage II Stage III

Moderate atrophy (score 2)(including incisura angularis) Stage II Stage II Stage III Stage IV

Severe atrophy (score 3)(including incisura angularis) Stage III Stage III Stage IV Stage IV

of the Sydney System and that atrophy is scored in a four-tiered scale (0ndash3) according to the visual analogue scale of theHouston-updated Sydney system The stage resulting fromthe combination of atrophic changes was assessed in the twomucosal compartments considered herein (Table 1)

7 Assessing Risks for Gastric CancerThe Epigenetic Bases of Chronic Gastritis

The molecular bases of the multistep process of gastriccarcinogenesis are highly relevant since it contributes greatlyto assess risks of gastric cancer Therefore chronic gastritisshould be understood as a disturbance in the balance betweentumor suppressor genes and oncogenes Many tumor sup-pressor genes have been identified in gastric cancer as wellas chronic gastritis [40] For example inactivation of p53tumor suppressor gene E-cadherin and DNA mismatchrepair genes (hMSH2 and hMLH1) responsible for loss ofheterozygosity (LOH) andmicrosatellite instability (MSI) arewell-recognized examples However multiple studies haveshown that mutation andor deletion is an infrequent mecha-nism of inactivating these well-established tumor suppressorgenes [41] In this scenario epigenetic alterations such as

DNA methylation have been proposed as an alternativemechanism for inactivation of tumor suppressor genes [41]DNA methylation is a process in which cytosines acquirea methyl group in 51015840 position only if they are followedby a guanine (CpG site) [42] Since DNA methylation hasbeen considered as an excellent candidate to explain howenvironmental factors may increase the risk of cancer ithas been proposed as a key element for the early events ofgastric carcinogenesis [43] For example Chan et al [44]found that DNA methylation of the promoter region of E-cadherin has been associated with H pylori infection Thisassociationwas independent of the age andor type of gastritis[44] Furthermore the same authors [45] also demonstratethat H pylori eradication with antibiotics reverses the DNAmethylation of E-cadherin (Figure 6) Similarly Maekita etal [46] analyzed the effect of H pylori infection on DNAmethylation for multiple genes (HAND1 HRASLS LOXp16 P41ARC and THBD) in H pylori negative and positivehealthy donors and gastric cancer patients Among healthydonors methylation levels were higher in H pylori positivesthan in H pylori negatives [46] Taken together these datasuggest that H pylori infection induces DNA methylationmostly in premalignant conditions rather than gastric canceritself [46] Among other tumor suppressor genes inactivated

6 Gastroenterology Research and Practice

Week 0Control Patient 1 Patient 2 Patient 3 Patient 4 Patient 5 Patient 6

MW U M U M U M U M U M U M U M

(a)

Week 0T ATGCGAGG TC GGG TGGGTGGGTCGTTAGTTT CG TTT T

(b)

Week 6Control Patient 1 Patient 2 Patient 3 Patient 4 Patient 5 Patient 6

MW U M U M U M U M U M U M U M

(c)

Week 6T GA TT G GT TGT GG T T GGT AGGT G AA TT T T TAG

(d)

Figure 6 CpG island methylation pattern at the E-cadherin gene in gastric mucosa from patients with dyspepsia (a) Before eradicationof H pylori (week 0) methylation was present in patients 3 5 and 6 (b) The methylated product was confirmed by sequencing using thesame methylated primer (c) After eradication of H pylori (week 6) methylation was not present in any patient (d) The methylated productwas again confirmed by sequencing using the same methylated primer No methylated cytosine was seen MW molecular weight marker Uunmethylated band M methylated band red color unmethylated cytosines converted to thymidine blue color methylated cytosines Takenfrom Chan and Rashid [45]

Controls NTAMs

p73

ATR-3IM-3CI-3OLGA stage-3OLGA stage-4

IM-0

ATR-0

CI-0

OLGA stage-0

Figure 7 Serial analysis formicroarray fromnontumor adjacentmucosa (NTAM) and chronic gastritis controls NTAMgroup is significantlycharacterized by the overexpression of p73 OLGA stages III to IV and severe atrophy (ATR-3) intestinal metaplasia (IM-3) and chronicinflammation (CI-3) according to the Sydney System Control group cases were significantly characterized by lack of intestinal metaplasia(IM-0) atrophy (ATR-0) and chronic inflammation (CI-0) False discovery rate = 0 Taken from Carrasco et al [51]

by DNAmethylation Reprimo (RPRM) a downstreammed-iator of p53-induced G2 cell cycle arrest [47] has beenrecently associated with more aggressive H pylori strains(cag-positive vacA s1m1 and EPIYA polymorphisms) inColombian residents from areas with high incidence ofgastric cancer [48] Furthermore we have identified thatDNA methylation of RPRM is not only found in gastricmucosa but also in the plasma of gastric cancer patients[49] Therefore this circulating cell-free DNA offers theopportunity for noninvasive assessing risks for gastric cancerSince a recent meta-analysis suggests that among severalcandidates circulating cell-free DNA of RPRM methylationis the most promising [50] this issue is currently underevaluation (Detection of Methylated Reprimo in Plasma forAsymptomatic Gastric Cancer DEMRAC study Finally we

have recently attempted to identify specific tissue biomarkersfor assessing the risk of premalignant gastritis [51] To thispurpose we evaluate the tissue overexpression as a conse-quence of DNA hypomethylation of several oncoproteinsassociated with gastric cancer including STAT1 p73 FHITp16INK4a BRCA1 HSP90 and EGFRThese tissue biomark-ers were compared with H pylori and the OLGA stagingsystem As expected severe atrophy and OLGA stage IVwere the most relevant histological features of premalignantgastritis Among tissue biomarkers overexpression of p73was the most relevant finding Both data were integratedby systems pathology approach by performing SignificanceAnalysis of Microarrays [52 53] This approach shows thatp73 is stronger as a single variable when compared withOLGA stage IV (Figure 7)Therefore we believe that gastritis

Gastroenterology Research and Practice 7

with severe atrophy has a greater risk for developing gastriccancer if in addition overexpress p73 [51]

In summary the role of H pylori in the development ofchronic gastritis is not only associated to the bacteria itselfbut also to host and environmental factors Assessing risks forgastric cancer can be achieved by the evaluation of clinicalmorphological and molecular factors Among morphologi-cal criteria atrophy and intestinalmetaplasia can be evaluatedvia Sydney and OLGA approaches Molecular factors thatshould be considered are mostly E-cadherin methylationcirculating cell-free DNA of RPRMmethylation and overex-pression of p73 Finally a system pathology approach allowsintegrating all these factors that might be useful in switchingfrom an interpretive and subjectivemorphologically orientedapproach to a more objective evidence-based tissue markerapproach

Acknowledgment

This paper is supported by Grants nos FondefD09I1137 andFondecyt1111014 from the Government of Chile to A HCorvalan

References

[1] N Figura and G Oderda ldquoReflections on the first descriptionof the presence of helicobacter species in the stomach ofmammalsrdquo Helicobacter vol 1 no 1 pp 4ndash5 1996

[2] M Kidd and I M Modlin ldquoA century of Helicobacter pyloriParadigms lostmdashparadigms regainedrdquo Digestion vol 59 no 1pp 1ndash15 1998

[3] R Schindler Gastritis William Heinmann London UK 1947[4] B J Marshall and J R Warren ldquoUnidentified curved bacilli in

the stomach of patients with gastritis and peptic ulcerationrdquoTheLancet vol 1 no 8390 pp 1311ndash1315 1984

[5] B C Jacobson JMCrawford and FA Farraye ldquoGI tract endo-scopic and tissue processing techniques and normal histologyin surgical pathology of the GI tractrdquo in Liver Biliary Tract andPancreas R D Odze and J R Goldblum Eds Elsevier 2009

[6] H M Malaty ldquoEpidemiology of Helicobacter pylori infectionrdquoBest Practice and Research vol 21 no 2 pp 205ndash214 2007

[7] T Shimizu T Akamatsu H Ota and T Katsuyama ldquoImmuno-histochemical detection of Helicobacter pylori in the surfacemucous gel layer and its clinicopathological significancerdquo Heli-cobacter vol 1 no 4 pp 197ndash206 1996

[8] F Carneiro E Fonseca and M Sobrinho-Simoes ldquoEpithelialdegeneration induced by Helicobacter pylorirdquo Human Pathol-ogy vol 23 no 11 pp 1314ndash1315 1992

[9] K M Leung P K Hui W Y Chan and T M M ThomasldquoHelicobacter pylori-related gastritis and gastric ulcer a contin-uum of progressive epithelial degenerationrdquo American Journalof Clinical Pathology vol 98 no 6 pp 569ndash574 1992

[10] R M Genta G M Lew and D Y Graham ldquoChanges in thegastric mucosa following eradication of Helicobacter pylorirdquoModern Pathology vol 6 no 3 pp 281ndash289 1993

[11] M F Dixon R M Genta J H Yardley and P Correa ldquoClassi-fication and grading of gastritis The updated Sydney systemInternational Workshop on the Histopathology of GastritisHouston 1994rdquoThe American Journal of Surgical Pathology vol20 no 10 pp 1161ndash1181 1996

[12] P Correa ldquoChronic gastritis a clinico-pathological classifica-tionrdquo American Journal of Gastroenterology vol 83 no 5 pp504ndash509 1988

[13] P Correa C Cuello E Duque et al ldquoGastric cancer in Colo-mbia III Natural history of precursor lesionsrdquo Journal of theNational Cancer Institute vol 57 no 5 pp 1027ndash1035 1976

[14] C Cuello P Correa W Haenszel et al ldquoGastric cancer inColombia I Cancer risk and suspect environmental agentsrdquoJournal of the National Cancer Institute vol 57 no 5 pp 1015ndash1020 1976

[15] W Haenszel P Correa C Cuello et al ldquoGastric cancer inColombia II Case control epidemiologic study of precursorlesionsrdquo Journal of the National Cancer Institute vol 57 no 5pp 1021ndash1026 1976

[16] P Correa W Haenszel C Cuello et al ldquoGastric precancerousprocess in a high risk population cohort follow-uprdquo CancerResearch vol 50 no 15 pp 4737ndash4740 1990

[17] H Ohata S Kitauchi N Yoshimura et al ldquoProgression ofchronic atrophic gastritis associated with Helicobacter pyloriinfection increases risk of gastric cancerrdquo International Journalof Cancer vol 109 no 1 pp 138ndash143 2004

[18] V Conteduca D Sansonno G Lauletta S Russi G Ingravalloand F Dammacco ldquoH pylori infection and gastric cancer stateof the art (Review)rdquo International Journal of Oncology vol 42no 1 pp 5ndash18 2013

[19] C A Gonzalez and A Agudo ldquoCarcinogenesis prevention andearly detection of gastric cancer where we are and where weshould gordquo International Journal of Cancer vol 130 no 4 pp745ndash753 2012

[20] P Correa and M B Piazuelo ldquoThe gastric precancerous cas-caderdquo Journal of Digestive Diseases vol 13 no 1 pp 2ndash9 2012

[21] R M Delahay and M Rugge ldquoPathogenesis of Helicobacterpylori infectionrdquo Helicobacter vol 17 supplement 1 pp 9ndash152012

[22] C A Gonzalez C Figueiredo C B Lic et al ldquoHelicobacterpylori cagA and vacA genotypes as predictors of progression ofgastric preneoplastic lesions a long-term follow-up in a high-risk area in Spainrdquo American Journal of Gastroenterology vol106 no 5 pp 867ndash874 2011

[23] E P Saraga D Gardiol and J Costa ldquoGastric dysplasia Ahistological follow-up studyrdquo American Journal of SurgicalPathology vol 11 no 10 pp 788ndash796 1987

[24] M J Coma del Corral F J Pardo-Mindan S Razquin and COjeda ldquoRisk of cancer in patients with gastric dysplasia follow-up study of 67 patientsrdquo Cancer vol 65 no 9 pp 2078ndash20851990

[25] H K Koch M Oehlert and W Oehlert ldquoAn evaluation ofgastric dysplasia in the years 1986 and 1987rdquo Pathology Researchand Practice vol 186 no 1 pp 80ndash84 1990

[26] J L Whiting A Sigurdsson D C Rowlands M T Hallisseyand J W L Fielding ldquoThe long term results of endoscopicsurveillance of premalignant gastric lesionsrdquo Gut vol 50 no3 pp 378ndash381 2002

[27] M Rugge M Cassaro F Di Mario et al ldquoThe long term out-come of gastric non-invasive neoplasiardquo Gut vol 52 no 8 pp1111ndash1116 2003

[28] KC R B RamesarD SA Sanders andDHopwood ldquoLimitedvalue of type III intestinalmetaplasia in predicting risk of gastriccarcinomardquo Journal of Clinical Pathology vol 40 no 11 pp1287ndash1290 1987

8 Gastroenterology Research and Practice

[29] S Silva M I Filipe and A Pinho ldquoVariants of intestinalmetaplasia in the evolution of chronic atrophic gastritis andgastric ulcer A follow up studyrdquo Gut vol 31 no 10 pp 1097ndash1104 1990

[30] T Rokkas M I Filipe and G E Sladen ldquoDetection of anincreased incidence of early gastric cancer in patients withintestinal metaplasia type III who are closely followed uprdquo Gutvol 32 no 10 pp 1110ndash1113 1991

[31] J M Conchillo G Houben A de Brune and R StockbruggerldquoIs type III intestinal metaplasia an obligatory precancerouslesion in intestinal-type gastric carcinomardquo European Journalof Cancer Prevention vol 10 no 4 pp 307ndash312 2001

[32] L Vannella E Lahner and B Annibale ldquoRisk for gastricneoplasias in patients with chronic atrophic gastritis a criticalreappraisalrdquo World Journal of Gastroenterology vol 18 no 12pp 1279ndash1285 2012

[33] M Rugge A Meggio G Pennelli et al ldquoGastritis staging inclinical practice the OLGA staging systemrdquo Gut vol 56 no 5pp 631ndash636 2007

[34] L G Capelle A C de Vries J Haringsma et al ldquoThe staging ofgastritis with the OLGA system by using intestinal metaplasiaas an accurate alternative for atrophic gastritisrdquoGastrointestinalEndoscopy vol 71 no 7 pp 1150ndash1158 2010

[35] M Rugge M de Boni G Pennelli et al ldquoGastritis OLGA-staging and gastric cancer risk a twelve-year clinico-patholog-ical follow-up studyrdquo Alimentary Pharmacology and Therapeu-tics vol 31 no 10 pp 1104ndash1111 2010

[36] M Rugge J G Kim V Mahachai et al ldquoOLGA gastritisstaging in young adults and country-specific gastric cancerriskrdquo International Journal of Surgical Pathology vol 16 no 2pp 150ndash154 2008

[37] G N Stemmermann ldquoIntestinal metaplasia of the stomach Astatus reportrdquo Cancer vol 74 no 2 pp 556ndash564 1994

[38] M Rugge M Fassan M Pizzi G Pennelli D Nitti and FFarinati ldquoOperative Link for Gastritis Assessment gastritisstaging incorporates intestinal metaplasia subtypingrdquo HumanPathology vol 42 no 10 pp 1539ndash1544 2011

[39] M Rugge P Correa M F Dixon et al ldquoGastric mucosal atro-phy interobserver consistency using new criteria for classifica-tion and gradingrdquo Alimentary Pharmacology and Therapeuticsvol 16 no 7 pp 1249ndash1259 2002

[40] W Yasui K Sentani N Sakamoto K Anami Y Naito andN Oue ldquoMolecular pathology of gastric cancer research andpracticerdquo Pathology Research and Practice vol 207 no 10 pp608ndash612 2011

[41] C O Gigek E S Chen D Q Calcagno F Wisnieski R RBurbano and M A Smith ldquoEpigenetic mechanisms in gastriccancerrdquo Epigenomics vol 4 no 3 pp 279ndash294 2012

[42] A H Corvalan and M J Maturana ldquoRecent patents of DNAmethylation biomarkers in gastrointestinal oncologyrdquo RecentPatents on DNA and Gene Sequences vol 4 no 3 pp 202ndash2092010

[43] C Zhao and X Bu ldquoPromoter methylation of tumor-relatedgenes in gastric carcinogenesisrdquo Histology and Histopathologyvol 27 no 10 pp 1271ndash1282 2012

[44] A O O Chan S K Lam B C YWong et al ldquoPromotermethy-lation of E-cadherin gene in gastric mucosa associated withHelicobacter pylori infection and in gastric cancerrdquoGut vol 52no 4 pp 502ndash506 2003

[45] A O O Chan and A Rashid ldquoCpG island methylation inprecursors of gastrointestinal malignanciesrdquo Current MolecularMedicine vol 6 no 4 pp 401ndash408 2006

[46] T Maekita K Nakazawa M Mihara et al ldquoHigh levels of aber-rant DNA methylation in Helicobacter pylori-infected gastricmucosae and its possible association with gastric cancer riskrdquoClinical Cancer Research vol 12 no 3 part 1 pp 989ndash995 2006

[47] R Ohki J Nemoto H Murasawa et al ldquoReprimo a new can-didate mediator of the p53-mediated cell cycle arrest at the G2phaserdquoThe Journal of Biological Chemistry vol 275 no 30 pp22627ndash22630 2000

[48] B G Schneider D F Peng M C Camargo et al ldquoPromoterDNAhypermethylation in gastric biopsies from subjects at highand low risk for gastric cancerrdquo International Journal of Cancervol 127 no 11 pp 2588ndash2597 2010

[49] C Bernal F Aguayo C Villarroel et al ldquoReprimo as a potentialbiomarker for early detection in gastric cancerrdquo Clinical CancerResearch vol 14 no 19 pp 6264ndash6269 2008

[50] N S Sapari M Loh A Vaithilingam and R Soong ldquoClinicalpotential of DNA methylation in gastric cancer a meta-analysisrdquo PLoS One vol 7 no 4 Article ID e36275 2012

[51] G Carrasco J Diaz J R Valbuena et al ldquoOverexpression ofp73 as a tissue marker for high-risk gastritisrdquo Clinical CancerResearch vol 16 no 12 pp 3253ndash3259 2010

[52] D Faratian ldquoSystems pathologyrdquo Breast Cancer Research vol12 supplement 4 article S4 2010

[53] A I Saeed N K Bhagabati J C Braisted et al ldquoTM4microar-ray software suiterdquoMethods in Enzymology vol 411 pp 134ndash1932006

Submit your manuscripts athttpwwwhindawicom

Stem CellsInternational

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

MEDIATORSINFLAMMATION

of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Behavioural Neurology

EndocrinologyInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Disease Markers

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

BioMed Research International

OncologyJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Oxidative Medicine and Cellular Longevity

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

PPAR Research

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Immunology ResearchHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Journal of

ObesityJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Computational and Mathematical Methods in Medicine

OphthalmologyJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Diabetes ResearchJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Research and TreatmentAIDS

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Gastroenterology Research and Practice

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Parkinsonrsquos Disease

Evidence-Based Complementary and Alternative Medicine

Volume 2014Hindawi Publishing Corporationhttpwwwhindawicom

Gastroenterology Research and Practice 5

(a) (b)

Figure 5 Atrophy is the loss of appropriate glands ((a) HampE 10x) Antral gastric mucosa with accentuated atrophy because replacementby extensive intestinal metaplasia ((b) HampE 10x square 20x) Fundic-corporal gastric mucosa with extensive loss of gastric glands partiallyreplaced by pseudo-pyloric metaplasia

Table 1TheOLGA staging frame Atrophy is scored as the percentage of atrophic glands and scored on a four-tiered scale No atrophy (0) =score 0 mild atrophy (1ndash30) = score 1 moderate atrophy (31ndash60) = score 2 9 severe atrophy (gt60) = score 3These scores (0ndash3) are usedin the OLGA staging assessment in each 10 compartment Taken from Rugge et al Dig Liver Dis 2011 43S373-84 with permission of Elsevier

CorpusAtrophy score No atrophy Mild atrophy Moderate atrophy Severe atrophy

(score 0) (score 1) (score 2) (score 3)

Antrum

No atrophy (score 0)(including incisura angularis) Stage 0 Stage I Stage II Stage II

Mild atrophy (score 1)(including incisura angularis) Stage I Stage I Stage II Stage III

Moderate atrophy (score 2)(including incisura angularis) Stage II Stage II Stage III Stage IV

Severe atrophy (score 3)(including incisura angularis) Stage III Stage III Stage IV Stage IV

of the Sydney System and that atrophy is scored in a four-tiered scale (0ndash3) according to the visual analogue scale of theHouston-updated Sydney system The stage resulting fromthe combination of atrophic changes was assessed in the twomucosal compartments considered herein (Table 1)

7 Assessing Risks for Gastric CancerThe Epigenetic Bases of Chronic Gastritis

The molecular bases of the multistep process of gastriccarcinogenesis are highly relevant since it contributes greatlyto assess risks of gastric cancer Therefore chronic gastritisshould be understood as a disturbance in the balance betweentumor suppressor genes and oncogenes Many tumor sup-pressor genes have been identified in gastric cancer as wellas chronic gastritis [40] For example inactivation of p53tumor suppressor gene E-cadherin and DNA mismatchrepair genes (hMSH2 and hMLH1) responsible for loss ofheterozygosity (LOH) andmicrosatellite instability (MSI) arewell-recognized examples However multiple studies haveshown that mutation andor deletion is an infrequent mecha-nism of inactivating these well-established tumor suppressorgenes [41] In this scenario epigenetic alterations such as

DNA methylation have been proposed as an alternativemechanism for inactivation of tumor suppressor genes [41]DNA methylation is a process in which cytosines acquirea methyl group in 51015840 position only if they are followedby a guanine (CpG site) [42] Since DNA methylation hasbeen considered as an excellent candidate to explain howenvironmental factors may increase the risk of cancer ithas been proposed as a key element for the early events ofgastric carcinogenesis [43] For example Chan et al [44]found that DNA methylation of the promoter region of E-cadherin has been associated with H pylori infection Thisassociationwas independent of the age andor type of gastritis[44] Furthermore the same authors [45] also demonstratethat H pylori eradication with antibiotics reverses the DNAmethylation of E-cadherin (Figure 6) Similarly Maekita etal [46] analyzed the effect of H pylori infection on DNAmethylation for multiple genes (HAND1 HRASLS LOXp16 P41ARC and THBD) in H pylori negative and positivehealthy donors and gastric cancer patients Among healthydonors methylation levels were higher in H pylori positivesthan in H pylori negatives [46] Taken together these datasuggest that H pylori infection induces DNA methylationmostly in premalignant conditions rather than gastric canceritself [46] Among other tumor suppressor genes inactivated

6 Gastroenterology Research and Practice

Week 0Control Patient 1 Patient 2 Patient 3 Patient 4 Patient 5 Patient 6

MW U M U M U M U M U M U M U M

(a)

Week 0T ATGCGAGG TC GGG TGGGTGGGTCGTTAGTTT CG TTT T

(b)

Week 6Control Patient 1 Patient 2 Patient 3 Patient 4 Patient 5 Patient 6

MW U M U M U M U M U M U M U M

(c)

Week 6T GA TT G GT TGT GG T T GGT AGGT G AA TT T T TAG

(d)

Figure 6 CpG island methylation pattern at the E-cadherin gene in gastric mucosa from patients with dyspepsia (a) Before eradicationof H pylori (week 0) methylation was present in patients 3 5 and 6 (b) The methylated product was confirmed by sequencing using thesame methylated primer (c) After eradication of H pylori (week 6) methylation was not present in any patient (d) The methylated productwas again confirmed by sequencing using the same methylated primer No methylated cytosine was seen MW molecular weight marker Uunmethylated band M methylated band red color unmethylated cytosines converted to thymidine blue color methylated cytosines Takenfrom Chan and Rashid [45]

Controls NTAMs

p73

ATR-3IM-3CI-3OLGA stage-3OLGA stage-4

IM-0

ATR-0

CI-0

OLGA stage-0

Figure 7 Serial analysis formicroarray fromnontumor adjacentmucosa (NTAM) and chronic gastritis controls NTAMgroup is significantlycharacterized by the overexpression of p73 OLGA stages III to IV and severe atrophy (ATR-3) intestinal metaplasia (IM-3) and chronicinflammation (CI-3) according to the Sydney System Control group cases were significantly characterized by lack of intestinal metaplasia(IM-0) atrophy (ATR-0) and chronic inflammation (CI-0) False discovery rate = 0 Taken from Carrasco et al [51]

by DNAmethylation Reprimo (RPRM) a downstreammed-iator of p53-induced G2 cell cycle arrest [47] has beenrecently associated with more aggressive H pylori strains(cag-positive vacA s1m1 and EPIYA polymorphisms) inColombian residents from areas with high incidence ofgastric cancer [48] Furthermore we have identified thatDNA methylation of RPRM is not only found in gastricmucosa but also in the plasma of gastric cancer patients[49] Therefore this circulating cell-free DNA offers theopportunity for noninvasive assessing risks for gastric cancerSince a recent meta-analysis suggests that among severalcandidates circulating cell-free DNA of RPRM methylationis the most promising [50] this issue is currently underevaluation (Detection of Methylated Reprimo in Plasma forAsymptomatic Gastric Cancer DEMRAC study Finally we

have recently attempted to identify specific tissue biomarkersfor assessing the risk of premalignant gastritis [51] To thispurpose we evaluate the tissue overexpression as a conse-quence of DNA hypomethylation of several oncoproteinsassociated with gastric cancer including STAT1 p73 FHITp16INK4a BRCA1 HSP90 and EGFRThese tissue biomark-ers were compared with H pylori and the OLGA stagingsystem As expected severe atrophy and OLGA stage IVwere the most relevant histological features of premalignantgastritis Among tissue biomarkers overexpression of p73was the most relevant finding Both data were integratedby systems pathology approach by performing SignificanceAnalysis of Microarrays [52 53] This approach shows thatp73 is stronger as a single variable when compared withOLGA stage IV (Figure 7)Therefore we believe that gastritis

Gastroenterology Research and Practice 7

with severe atrophy has a greater risk for developing gastriccancer if in addition overexpress p73 [51]

In summary the role of H pylori in the development ofchronic gastritis is not only associated to the bacteria itselfbut also to host and environmental factors Assessing risks forgastric cancer can be achieved by the evaluation of clinicalmorphological and molecular factors Among morphologi-cal criteria atrophy and intestinalmetaplasia can be evaluatedvia Sydney and OLGA approaches Molecular factors thatshould be considered are mostly E-cadherin methylationcirculating cell-free DNA of RPRMmethylation and overex-pression of p73 Finally a system pathology approach allowsintegrating all these factors that might be useful in switchingfrom an interpretive and subjectivemorphologically orientedapproach to a more objective evidence-based tissue markerapproach

Acknowledgment

This paper is supported by Grants nos FondefD09I1137 andFondecyt1111014 from the Government of Chile to A HCorvalan

References

[1] N Figura and G Oderda ldquoReflections on the first descriptionof the presence of helicobacter species in the stomach ofmammalsrdquo Helicobacter vol 1 no 1 pp 4ndash5 1996

[2] M Kidd and I M Modlin ldquoA century of Helicobacter pyloriParadigms lostmdashparadigms regainedrdquo Digestion vol 59 no 1pp 1ndash15 1998

[3] R Schindler Gastritis William Heinmann London UK 1947[4] B J Marshall and J R Warren ldquoUnidentified curved bacilli in

the stomach of patients with gastritis and peptic ulcerationrdquoTheLancet vol 1 no 8390 pp 1311ndash1315 1984

[5] B C Jacobson JMCrawford and FA Farraye ldquoGI tract endo-scopic and tissue processing techniques and normal histologyin surgical pathology of the GI tractrdquo in Liver Biliary Tract andPancreas R D Odze and J R Goldblum Eds Elsevier 2009

[6] H M Malaty ldquoEpidemiology of Helicobacter pylori infectionrdquoBest Practice and Research vol 21 no 2 pp 205ndash214 2007

[7] T Shimizu T Akamatsu H Ota and T Katsuyama ldquoImmuno-histochemical detection of Helicobacter pylori in the surfacemucous gel layer and its clinicopathological significancerdquo Heli-cobacter vol 1 no 4 pp 197ndash206 1996

[8] F Carneiro E Fonseca and M Sobrinho-Simoes ldquoEpithelialdegeneration induced by Helicobacter pylorirdquo Human Pathol-ogy vol 23 no 11 pp 1314ndash1315 1992

[9] K M Leung P K Hui W Y Chan and T M M ThomasldquoHelicobacter pylori-related gastritis and gastric ulcer a contin-uum of progressive epithelial degenerationrdquo American Journalof Clinical Pathology vol 98 no 6 pp 569ndash574 1992

[10] R M Genta G M Lew and D Y Graham ldquoChanges in thegastric mucosa following eradication of Helicobacter pylorirdquoModern Pathology vol 6 no 3 pp 281ndash289 1993

[11] M F Dixon R M Genta J H Yardley and P Correa ldquoClassi-fication and grading of gastritis The updated Sydney systemInternational Workshop on the Histopathology of GastritisHouston 1994rdquoThe American Journal of Surgical Pathology vol20 no 10 pp 1161ndash1181 1996

[12] P Correa ldquoChronic gastritis a clinico-pathological classifica-tionrdquo American Journal of Gastroenterology vol 83 no 5 pp504ndash509 1988

[13] P Correa C Cuello E Duque et al ldquoGastric cancer in Colo-mbia III Natural history of precursor lesionsrdquo Journal of theNational Cancer Institute vol 57 no 5 pp 1027ndash1035 1976

[14] C Cuello P Correa W Haenszel et al ldquoGastric cancer inColombia I Cancer risk and suspect environmental agentsrdquoJournal of the National Cancer Institute vol 57 no 5 pp 1015ndash1020 1976

[15] W Haenszel P Correa C Cuello et al ldquoGastric cancer inColombia II Case control epidemiologic study of precursorlesionsrdquo Journal of the National Cancer Institute vol 57 no 5pp 1021ndash1026 1976

[16] P Correa W Haenszel C Cuello et al ldquoGastric precancerousprocess in a high risk population cohort follow-uprdquo CancerResearch vol 50 no 15 pp 4737ndash4740 1990

[17] H Ohata S Kitauchi N Yoshimura et al ldquoProgression ofchronic atrophic gastritis associated with Helicobacter pyloriinfection increases risk of gastric cancerrdquo International Journalof Cancer vol 109 no 1 pp 138ndash143 2004

[18] V Conteduca D Sansonno G Lauletta S Russi G Ingravalloand F Dammacco ldquoH pylori infection and gastric cancer stateof the art (Review)rdquo International Journal of Oncology vol 42no 1 pp 5ndash18 2013

[19] C A Gonzalez and A Agudo ldquoCarcinogenesis prevention andearly detection of gastric cancer where we are and where weshould gordquo International Journal of Cancer vol 130 no 4 pp745ndash753 2012

[20] P Correa and M B Piazuelo ldquoThe gastric precancerous cas-caderdquo Journal of Digestive Diseases vol 13 no 1 pp 2ndash9 2012

[21] R M Delahay and M Rugge ldquoPathogenesis of Helicobacterpylori infectionrdquo Helicobacter vol 17 supplement 1 pp 9ndash152012

[22] C A Gonzalez C Figueiredo C B Lic et al ldquoHelicobacterpylori cagA and vacA genotypes as predictors of progression ofgastric preneoplastic lesions a long-term follow-up in a high-risk area in Spainrdquo American Journal of Gastroenterology vol106 no 5 pp 867ndash874 2011

[23] E P Saraga D Gardiol and J Costa ldquoGastric dysplasia Ahistological follow-up studyrdquo American Journal of SurgicalPathology vol 11 no 10 pp 788ndash796 1987

[24] M J Coma del Corral F J Pardo-Mindan S Razquin and COjeda ldquoRisk of cancer in patients with gastric dysplasia follow-up study of 67 patientsrdquo Cancer vol 65 no 9 pp 2078ndash20851990

[25] H K Koch M Oehlert and W Oehlert ldquoAn evaluation ofgastric dysplasia in the years 1986 and 1987rdquo Pathology Researchand Practice vol 186 no 1 pp 80ndash84 1990

[26] J L Whiting A Sigurdsson D C Rowlands M T Hallisseyand J W L Fielding ldquoThe long term results of endoscopicsurveillance of premalignant gastric lesionsrdquo Gut vol 50 no3 pp 378ndash381 2002

[27] M Rugge M Cassaro F Di Mario et al ldquoThe long term out-come of gastric non-invasive neoplasiardquo Gut vol 52 no 8 pp1111ndash1116 2003

[28] KC R B RamesarD SA Sanders andDHopwood ldquoLimitedvalue of type III intestinalmetaplasia in predicting risk of gastriccarcinomardquo Journal of Clinical Pathology vol 40 no 11 pp1287ndash1290 1987

8 Gastroenterology Research and Practice

[29] S Silva M I Filipe and A Pinho ldquoVariants of intestinalmetaplasia in the evolution of chronic atrophic gastritis andgastric ulcer A follow up studyrdquo Gut vol 31 no 10 pp 1097ndash1104 1990

[30] T Rokkas M I Filipe and G E Sladen ldquoDetection of anincreased incidence of early gastric cancer in patients withintestinal metaplasia type III who are closely followed uprdquo Gutvol 32 no 10 pp 1110ndash1113 1991

[31] J M Conchillo G Houben A de Brune and R StockbruggerldquoIs type III intestinal metaplasia an obligatory precancerouslesion in intestinal-type gastric carcinomardquo European Journalof Cancer Prevention vol 10 no 4 pp 307ndash312 2001

[32] L Vannella E Lahner and B Annibale ldquoRisk for gastricneoplasias in patients with chronic atrophic gastritis a criticalreappraisalrdquo World Journal of Gastroenterology vol 18 no 12pp 1279ndash1285 2012

[33] M Rugge A Meggio G Pennelli et al ldquoGastritis staging inclinical practice the OLGA staging systemrdquo Gut vol 56 no 5pp 631ndash636 2007

[34] L G Capelle A C de Vries J Haringsma et al ldquoThe staging ofgastritis with the OLGA system by using intestinal metaplasiaas an accurate alternative for atrophic gastritisrdquoGastrointestinalEndoscopy vol 71 no 7 pp 1150ndash1158 2010

[35] M Rugge M de Boni G Pennelli et al ldquoGastritis OLGA-staging and gastric cancer risk a twelve-year clinico-patholog-ical follow-up studyrdquo Alimentary Pharmacology and Therapeu-tics vol 31 no 10 pp 1104ndash1111 2010

[36] M Rugge J G Kim V Mahachai et al ldquoOLGA gastritisstaging in young adults and country-specific gastric cancerriskrdquo International Journal of Surgical Pathology vol 16 no 2pp 150ndash154 2008

[37] G N Stemmermann ldquoIntestinal metaplasia of the stomach Astatus reportrdquo Cancer vol 74 no 2 pp 556ndash564 1994

[38] M Rugge M Fassan M Pizzi G Pennelli D Nitti and FFarinati ldquoOperative Link for Gastritis Assessment gastritisstaging incorporates intestinal metaplasia subtypingrdquo HumanPathology vol 42 no 10 pp 1539ndash1544 2011

[39] M Rugge P Correa M F Dixon et al ldquoGastric mucosal atro-phy interobserver consistency using new criteria for classifica-tion and gradingrdquo Alimentary Pharmacology and Therapeuticsvol 16 no 7 pp 1249ndash1259 2002

[40] W Yasui K Sentani N Sakamoto K Anami Y Naito andN Oue ldquoMolecular pathology of gastric cancer research andpracticerdquo Pathology Research and Practice vol 207 no 10 pp608ndash612 2011

[41] C O Gigek E S Chen D Q Calcagno F Wisnieski R RBurbano and M A Smith ldquoEpigenetic mechanisms in gastriccancerrdquo Epigenomics vol 4 no 3 pp 279ndash294 2012

[42] A H Corvalan and M J Maturana ldquoRecent patents of DNAmethylation biomarkers in gastrointestinal oncologyrdquo RecentPatents on DNA and Gene Sequences vol 4 no 3 pp 202ndash2092010

[43] C Zhao and X Bu ldquoPromoter methylation of tumor-relatedgenes in gastric carcinogenesisrdquo Histology and Histopathologyvol 27 no 10 pp 1271ndash1282 2012

[44] A O O Chan S K Lam B C YWong et al ldquoPromotermethy-lation of E-cadherin gene in gastric mucosa associated withHelicobacter pylori infection and in gastric cancerrdquoGut vol 52no 4 pp 502ndash506 2003

[45] A O O Chan and A Rashid ldquoCpG island methylation inprecursors of gastrointestinal malignanciesrdquo Current MolecularMedicine vol 6 no 4 pp 401ndash408 2006

[46] T Maekita K Nakazawa M Mihara et al ldquoHigh levels of aber-rant DNA methylation in Helicobacter pylori-infected gastricmucosae and its possible association with gastric cancer riskrdquoClinical Cancer Research vol 12 no 3 part 1 pp 989ndash995 2006

[47] R Ohki J Nemoto H Murasawa et al ldquoReprimo a new can-didate mediator of the p53-mediated cell cycle arrest at the G2phaserdquoThe Journal of Biological Chemistry vol 275 no 30 pp22627ndash22630 2000

[48] B G Schneider D F Peng M C Camargo et al ldquoPromoterDNAhypermethylation in gastric biopsies from subjects at highand low risk for gastric cancerrdquo International Journal of Cancervol 127 no 11 pp 2588ndash2597 2010

[49] C Bernal F Aguayo C Villarroel et al ldquoReprimo as a potentialbiomarker for early detection in gastric cancerrdquo Clinical CancerResearch vol 14 no 19 pp 6264ndash6269 2008

[50] N S Sapari M Loh A Vaithilingam and R Soong ldquoClinicalpotential of DNA methylation in gastric cancer a meta-analysisrdquo PLoS One vol 7 no 4 Article ID e36275 2012

[51] G Carrasco J Diaz J R Valbuena et al ldquoOverexpression ofp73 as a tissue marker for high-risk gastritisrdquo Clinical CancerResearch vol 16 no 12 pp 3253ndash3259 2010

[52] D Faratian ldquoSystems pathologyrdquo Breast Cancer Research vol12 supplement 4 article S4 2010

[53] A I Saeed N K Bhagabati J C Braisted et al ldquoTM4microar-ray software suiterdquoMethods in Enzymology vol 411 pp 134ndash1932006

Submit your manuscripts athttpwwwhindawicom

Stem CellsInternational

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

MEDIATORSINFLAMMATION

of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Behavioural Neurology

EndocrinologyInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Disease Markers

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

BioMed Research International

OncologyJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Oxidative Medicine and Cellular Longevity

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

PPAR Research

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Immunology ResearchHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Journal of

ObesityJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Computational and Mathematical Methods in Medicine

OphthalmologyJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Diabetes ResearchJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Research and TreatmentAIDS

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Gastroenterology Research and Practice

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Parkinsonrsquos Disease

Evidence-Based Complementary and Alternative Medicine

Volume 2014Hindawi Publishing Corporationhttpwwwhindawicom

6 Gastroenterology Research and Practice

Week 0Control Patient 1 Patient 2 Patient 3 Patient 4 Patient 5 Patient 6

MW U M U M U M U M U M U M U M

(a)

Week 0T ATGCGAGG TC GGG TGGGTGGGTCGTTAGTTT CG TTT T

(b)

Week 6Control Patient 1 Patient 2 Patient 3 Patient 4 Patient 5 Patient 6

MW U M U M U M U M U M U M U M

(c)

Week 6T GA TT G GT TGT GG T T GGT AGGT G AA TT T T TAG

(d)

Figure 6 CpG island methylation pattern at the E-cadherin gene in gastric mucosa from patients with dyspepsia (a) Before eradicationof H pylori (week 0) methylation was present in patients 3 5 and 6 (b) The methylated product was confirmed by sequencing using thesame methylated primer (c) After eradication of H pylori (week 6) methylation was not present in any patient (d) The methylated productwas again confirmed by sequencing using the same methylated primer No methylated cytosine was seen MW molecular weight marker Uunmethylated band M methylated band red color unmethylated cytosines converted to thymidine blue color methylated cytosines Takenfrom Chan and Rashid [45]

Controls NTAMs

p73

ATR-3IM-3CI-3OLGA stage-3OLGA stage-4

IM-0

ATR-0

CI-0

OLGA stage-0

Figure 7 Serial analysis formicroarray fromnontumor adjacentmucosa (NTAM) and chronic gastritis controls NTAMgroup is significantlycharacterized by the overexpression of p73 OLGA stages III to IV and severe atrophy (ATR-3) intestinal metaplasia (IM-3) and chronicinflammation (CI-3) according to the Sydney System Control group cases were significantly characterized by lack of intestinal metaplasia(IM-0) atrophy (ATR-0) and chronic inflammation (CI-0) False discovery rate = 0 Taken from Carrasco et al [51]

by DNAmethylation Reprimo (RPRM) a downstreammed-iator of p53-induced G2 cell cycle arrest [47] has beenrecently associated with more aggressive H pylori strains(cag-positive vacA s1m1 and EPIYA polymorphisms) inColombian residents from areas with high incidence ofgastric cancer [48] Furthermore we have identified thatDNA methylation of RPRM is not only found in gastricmucosa but also in the plasma of gastric cancer patients[49] Therefore this circulating cell-free DNA offers theopportunity for noninvasive assessing risks for gastric cancerSince a recent meta-analysis suggests that among severalcandidates circulating cell-free DNA of RPRM methylationis the most promising [50] this issue is currently underevaluation (Detection of Methylated Reprimo in Plasma forAsymptomatic Gastric Cancer DEMRAC study Finally we

have recently attempted to identify specific tissue biomarkersfor assessing the risk of premalignant gastritis [51] To thispurpose we evaluate the tissue overexpression as a conse-quence of DNA hypomethylation of several oncoproteinsassociated with gastric cancer including STAT1 p73 FHITp16INK4a BRCA1 HSP90 and EGFRThese tissue biomark-ers were compared with H pylori and the OLGA stagingsystem As expected severe atrophy and OLGA stage IVwere the most relevant histological features of premalignantgastritis Among tissue biomarkers overexpression of p73was the most relevant finding Both data were integratedby systems pathology approach by performing SignificanceAnalysis of Microarrays [52 53] This approach shows thatp73 is stronger as a single variable when compared withOLGA stage IV (Figure 7)Therefore we believe that gastritis

Gastroenterology Research and Practice 7

with severe atrophy has a greater risk for developing gastriccancer if in addition overexpress p73 [51]

In summary the role of H pylori in the development ofchronic gastritis is not only associated to the bacteria itselfbut also to host and environmental factors Assessing risks forgastric cancer can be achieved by the evaluation of clinicalmorphological and molecular factors Among morphologi-cal criteria atrophy and intestinalmetaplasia can be evaluatedvia Sydney and OLGA approaches Molecular factors thatshould be considered are mostly E-cadherin methylationcirculating cell-free DNA of RPRMmethylation and overex-pression of p73 Finally a system pathology approach allowsintegrating all these factors that might be useful in switchingfrom an interpretive and subjectivemorphologically orientedapproach to a more objective evidence-based tissue markerapproach

Acknowledgment

This paper is supported by Grants nos FondefD09I1137 andFondecyt1111014 from the Government of Chile to A HCorvalan

References

[1] N Figura and G Oderda ldquoReflections on the first descriptionof the presence of helicobacter species in the stomach ofmammalsrdquo Helicobacter vol 1 no 1 pp 4ndash5 1996

[2] M Kidd and I M Modlin ldquoA century of Helicobacter pyloriParadigms lostmdashparadigms regainedrdquo Digestion vol 59 no 1pp 1ndash15 1998

[3] R Schindler Gastritis William Heinmann London UK 1947[4] B J Marshall and J R Warren ldquoUnidentified curved bacilli in

the stomach of patients with gastritis and peptic ulcerationrdquoTheLancet vol 1 no 8390 pp 1311ndash1315 1984

[5] B C Jacobson JMCrawford and FA Farraye ldquoGI tract endo-scopic and tissue processing techniques and normal histologyin surgical pathology of the GI tractrdquo in Liver Biliary Tract andPancreas R D Odze and J R Goldblum Eds Elsevier 2009

[6] H M Malaty ldquoEpidemiology of Helicobacter pylori infectionrdquoBest Practice and Research vol 21 no 2 pp 205ndash214 2007

[7] T Shimizu T Akamatsu H Ota and T Katsuyama ldquoImmuno-histochemical detection of Helicobacter pylori in the surfacemucous gel layer and its clinicopathological significancerdquo Heli-cobacter vol 1 no 4 pp 197ndash206 1996

[8] F Carneiro E Fonseca and M Sobrinho-Simoes ldquoEpithelialdegeneration induced by Helicobacter pylorirdquo Human Pathol-ogy vol 23 no 11 pp 1314ndash1315 1992

[9] K M Leung P K Hui W Y Chan and T M M ThomasldquoHelicobacter pylori-related gastritis and gastric ulcer a contin-uum of progressive epithelial degenerationrdquo American Journalof Clinical Pathology vol 98 no 6 pp 569ndash574 1992

[10] R M Genta G M Lew and D Y Graham ldquoChanges in thegastric mucosa following eradication of Helicobacter pylorirdquoModern Pathology vol 6 no 3 pp 281ndash289 1993

[11] M F Dixon R M Genta J H Yardley and P Correa ldquoClassi-fication and grading of gastritis The updated Sydney systemInternational Workshop on the Histopathology of GastritisHouston 1994rdquoThe American Journal of Surgical Pathology vol20 no 10 pp 1161ndash1181 1996

[12] P Correa ldquoChronic gastritis a clinico-pathological classifica-tionrdquo American Journal of Gastroenterology vol 83 no 5 pp504ndash509 1988

[13] P Correa C Cuello E Duque et al ldquoGastric cancer in Colo-mbia III Natural history of precursor lesionsrdquo Journal of theNational Cancer Institute vol 57 no 5 pp 1027ndash1035 1976

[14] C Cuello P Correa W Haenszel et al ldquoGastric cancer inColombia I Cancer risk and suspect environmental agentsrdquoJournal of the National Cancer Institute vol 57 no 5 pp 1015ndash1020 1976

[15] W Haenszel P Correa C Cuello et al ldquoGastric cancer inColombia II Case control epidemiologic study of precursorlesionsrdquo Journal of the National Cancer Institute vol 57 no 5pp 1021ndash1026 1976

[16] P Correa W Haenszel C Cuello et al ldquoGastric precancerousprocess in a high risk population cohort follow-uprdquo CancerResearch vol 50 no 15 pp 4737ndash4740 1990

[17] H Ohata S Kitauchi N Yoshimura et al ldquoProgression ofchronic atrophic gastritis associated with Helicobacter pyloriinfection increases risk of gastric cancerrdquo International Journalof Cancer vol 109 no 1 pp 138ndash143 2004

[18] V Conteduca D Sansonno G Lauletta S Russi G Ingravalloand F Dammacco ldquoH pylori infection and gastric cancer stateof the art (Review)rdquo International Journal of Oncology vol 42no 1 pp 5ndash18 2013

[19] C A Gonzalez and A Agudo ldquoCarcinogenesis prevention andearly detection of gastric cancer where we are and where weshould gordquo International Journal of Cancer vol 130 no 4 pp745ndash753 2012

[20] P Correa and M B Piazuelo ldquoThe gastric precancerous cas-caderdquo Journal of Digestive Diseases vol 13 no 1 pp 2ndash9 2012

[21] R M Delahay and M Rugge ldquoPathogenesis of Helicobacterpylori infectionrdquo Helicobacter vol 17 supplement 1 pp 9ndash152012

[22] C A Gonzalez C Figueiredo C B Lic et al ldquoHelicobacterpylori cagA and vacA genotypes as predictors of progression ofgastric preneoplastic lesions a long-term follow-up in a high-risk area in Spainrdquo American Journal of Gastroenterology vol106 no 5 pp 867ndash874 2011

[23] E P Saraga D Gardiol and J Costa ldquoGastric dysplasia Ahistological follow-up studyrdquo American Journal of SurgicalPathology vol 11 no 10 pp 788ndash796 1987

[24] M J Coma del Corral F J Pardo-Mindan S Razquin and COjeda ldquoRisk of cancer in patients with gastric dysplasia follow-up study of 67 patientsrdquo Cancer vol 65 no 9 pp 2078ndash20851990

[25] H K Koch M Oehlert and W Oehlert ldquoAn evaluation ofgastric dysplasia in the years 1986 and 1987rdquo Pathology Researchand Practice vol 186 no 1 pp 80ndash84 1990

[26] J L Whiting A Sigurdsson D C Rowlands M T Hallisseyand J W L Fielding ldquoThe long term results of endoscopicsurveillance of premalignant gastric lesionsrdquo Gut vol 50 no3 pp 378ndash381 2002

[27] M Rugge M Cassaro F Di Mario et al ldquoThe long term out-come of gastric non-invasive neoplasiardquo Gut vol 52 no 8 pp1111ndash1116 2003

[28] KC R B RamesarD SA Sanders andDHopwood ldquoLimitedvalue of type III intestinalmetaplasia in predicting risk of gastriccarcinomardquo Journal of Clinical Pathology vol 40 no 11 pp1287ndash1290 1987

8 Gastroenterology Research and Practice

[29] S Silva M I Filipe and A Pinho ldquoVariants of intestinalmetaplasia in the evolution of chronic atrophic gastritis andgastric ulcer A follow up studyrdquo Gut vol 31 no 10 pp 1097ndash1104 1990

[30] T Rokkas M I Filipe and G E Sladen ldquoDetection of anincreased incidence of early gastric cancer in patients withintestinal metaplasia type III who are closely followed uprdquo Gutvol 32 no 10 pp 1110ndash1113 1991

[31] J M Conchillo G Houben A de Brune and R StockbruggerldquoIs type III intestinal metaplasia an obligatory precancerouslesion in intestinal-type gastric carcinomardquo European Journalof Cancer Prevention vol 10 no 4 pp 307ndash312 2001

[32] L Vannella E Lahner and B Annibale ldquoRisk for gastricneoplasias in patients with chronic atrophic gastritis a criticalreappraisalrdquo World Journal of Gastroenterology vol 18 no 12pp 1279ndash1285 2012

[33] M Rugge A Meggio G Pennelli et al ldquoGastritis staging inclinical practice the OLGA staging systemrdquo Gut vol 56 no 5pp 631ndash636 2007

[34] L G Capelle A C de Vries J Haringsma et al ldquoThe staging ofgastritis with the OLGA system by using intestinal metaplasiaas an accurate alternative for atrophic gastritisrdquoGastrointestinalEndoscopy vol 71 no 7 pp 1150ndash1158 2010

[35] M Rugge M de Boni G Pennelli et al ldquoGastritis OLGA-staging and gastric cancer risk a twelve-year clinico-patholog-ical follow-up studyrdquo Alimentary Pharmacology and Therapeu-tics vol 31 no 10 pp 1104ndash1111 2010

[36] M Rugge J G Kim V Mahachai et al ldquoOLGA gastritisstaging in young adults and country-specific gastric cancerriskrdquo International Journal of Surgical Pathology vol 16 no 2pp 150ndash154 2008

[37] G N Stemmermann ldquoIntestinal metaplasia of the stomach Astatus reportrdquo Cancer vol 74 no 2 pp 556ndash564 1994

[38] M Rugge M Fassan M Pizzi G Pennelli D Nitti and FFarinati ldquoOperative Link for Gastritis Assessment gastritisstaging incorporates intestinal metaplasia subtypingrdquo HumanPathology vol 42 no 10 pp 1539ndash1544 2011

[39] M Rugge P Correa M F Dixon et al ldquoGastric mucosal atro-phy interobserver consistency using new criteria for classifica-tion and gradingrdquo Alimentary Pharmacology and Therapeuticsvol 16 no 7 pp 1249ndash1259 2002

[40] W Yasui K Sentani N Sakamoto K Anami Y Naito andN Oue ldquoMolecular pathology of gastric cancer research andpracticerdquo Pathology Research and Practice vol 207 no 10 pp608ndash612 2011

[41] C O Gigek E S Chen D Q Calcagno F Wisnieski R RBurbano and M A Smith ldquoEpigenetic mechanisms in gastriccancerrdquo Epigenomics vol 4 no 3 pp 279ndash294 2012

[42] A H Corvalan and M J Maturana ldquoRecent patents of DNAmethylation biomarkers in gastrointestinal oncologyrdquo RecentPatents on DNA and Gene Sequences vol 4 no 3 pp 202ndash2092010

[43] C Zhao and X Bu ldquoPromoter methylation of tumor-relatedgenes in gastric carcinogenesisrdquo Histology and Histopathologyvol 27 no 10 pp 1271ndash1282 2012

[44] A O O Chan S K Lam B C YWong et al ldquoPromotermethy-lation of E-cadherin gene in gastric mucosa associated withHelicobacter pylori infection and in gastric cancerrdquoGut vol 52no 4 pp 502ndash506 2003

[45] A O O Chan and A Rashid ldquoCpG island methylation inprecursors of gastrointestinal malignanciesrdquo Current MolecularMedicine vol 6 no 4 pp 401ndash408 2006

[46] T Maekita K Nakazawa M Mihara et al ldquoHigh levels of aber-rant DNA methylation in Helicobacter pylori-infected gastricmucosae and its possible association with gastric cancer riskrdquoClinical Cancer Research vol 12 no 3 part 1 pp 989ndash995 2006

[47] R Ohki J Nemoto H Murasawa et al ldquoReprimo a new can-didate mediator of the p53-mediated cell cycle arrest at the G2phaserdquoThe Journal of Biological Chemistry vol 275 no 30 pp22627ndash22630 2000

[48] B G Schneider D F Peng M C Camargo et al ldquoPromoterDNAhypermethylation in gastric biopsies from subjects at highand low risk for gastric cancerrdquo International Journal of Cancervol 127 no 11 pp 2588ndash2597 2010

[49] C Bernal F Aguayo C Villarroel et al ldquoReprimo as a potentialbiomarker for early detection in gastric cancerrdquo Clinical CancerResearch vol 14 no 19 pp 6264ndash6269 2008

[50] N S Sapari M Loh A Vaithilingam and R Soong ldquoClinicalpotential of DNA methylation in gastric cancer a meta-analysisrdquo PLoS One vol 7 no 4 Article ID e36275 2012

[51] G Carrasco J Diaz J R Valbuena et al ldquoOverexpression ofp73 as a tissue marker for high-risk gastritisrdquo Clinical CancerResearch vol 16 no 12 pp 3253ndash3259 2010

[52] D Faratian ldquoSystems pathologyrdquo Breast Cancer Research vol12 supplement 4 article S4 2010

[53] A I Saeed N K Bhagabati J C Braisted et al ldquoTM4microar-ray software suiterdquoMethods in Enzymology vol 411 pp 134ndash1932006

Submit your manuscripts athttpwwwhindawicom

Stem CellsInternational

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

MEDIATORSINFLAMMATION

of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Behavioural Neurology

EndocrinologyInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Disease Markers

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

BioMed Research International

OncologyJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Oxidative Medicine and Cellular Longevity

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

PPAR Research

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Immunology ResearchHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Journal of

ObesityJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Computational and Mathematical Methods in Medicine

OphthalmologyJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Diabetes ResearchJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Research and TreatmentAIDS

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Gastroenterology Research and Practice

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Parkinsonrsquos Disease

Evidence-Based Complementary and Alternative Medicine

Volume 2014Hindawi Publishing Corporationhttpwwwhindawicom

Gastroenterology Research and Practice 7

with severe atrophy has a greater risk for developing gastriccancer if in addition overexpress p73 [51]

In summary the role of H pylori in the development ofchronic gastritis is not only associated to the bacteria itselfbut also to host and environmental factors Assessing risks forgastric cancer can be achieved by the evaluation of clinicalmorphological and molecular factors Among morphologi-cal criteria atrophy and intestinalmetaplasia can be evaluatedvia Sydney and OLGA approaches Molecular factors thatshould be considered are mostly E-cadherin methylationcirculating cell-free DNA of RPRMmethylation and overex-pression of p73 Finally a system pathology approach allowsintegrating all these factors that might be useful in switchingfrom an interpretive and subjectivemorphologically orientedapproach to a more objective evidence-based tissue markerapproach

Acknowledgment

This paper is supported by Grants nos FondefD09I1137 andFondecyt1111014 from the Government of Chile to A HCorvalan

References

[1] N Figura and G Oderda ldquoReflections on the first descriptionof the presence of helicobacter species in the stomach ofmammalsrdquo Helicobacter vol 1 no 1 pp 4ndash5 1996

[2] M Kidd and I M Modlin ldquoA century of Helicobacter pyloriParadigms lostmdashparadigms regainedrdquo Digestion vol 59 no 1pp 1ndash15 1998

[3] R Schindler Gastritis William Heinmann London UK 1947[4] B J Marshall and J R Warren ldquoUnidentified curved bacilli in

the stomach of patients with gastritis and peptic ulcerationrdquoTheLancet vol 1 no 8390 pp 1311ndash1315 1984

[5] B C Jacobson JMCrawford and FA Farraye ldquoGI tract endo-scopic and tissue processing techniques and normal histologyin surgical pathology of the GI tractrdquo in Liver Biliary Tract andPancreas R D Odze and J R Goldblum Eds Elsevier 2009

[6] H M Malaty ldquoEpidemiology of Helicobacter pylori infectionrdquoBest Practice and Research vol 21 no 2 pp 205ndash214 2007

[7] T Shimizu T Akamatsu H Ota and T Katsuyama ldquoImmuno-histochemical detection of Helicobacter pylori in the surfacemucous gel layer and its clinicopathological significancerdquo Heli-cobacter vol 1 no 4 pp 197ndash206 1996

[8] F Carneiro E Fonseca and M Sobrinho-Simoes ldquoEpithelialdegeneration induced by Helicobacter pylorirdquo Human Pathol-ogy vol 23 no 11 pp 1314ndash1315 1992

[9] K M Leung P K Hui W Y Chan and T M M ThomasldquoHelicobacter pylori-related gastritis and gastric ulcer a contin-uum of progressive epithelial degenerationrdquo American Journalof Clinical Pathology vol 98 no 6 pp 569ndash574 1992

[10] R M Genta G M Lew and D Y Graham ldquoChanges in thegastric mucosa following eradication of Helicobacter pylorirdquoModern Pathology vol 6 no 3 pp 281ndash289 1993

[11] M F Dixon R M Genta J H Yardley and P Correa ldquoClassi-fication and grading of gastritis The updated Sydney systemInternational Workshop on the Histopathology of GastritisHouston 1994rdquoThe American Journal of Surgical Pathology vol20 no 10 pp 1161ndash1181 1996

[12] P Correa ldquoChronic gastritis a clinico-pathological classifica-tionrdquo American Journal of Gastroenterology vol 83 no 5 pp504ndash509 1988

[13] P Correa C Cuello E Duque et al ldquoGastric cancer in Colo-mbia III Natural history of precursor lesionsrdquo Journal of theNational Cancer Institute vol 57 no 5 pp 1027ndash1035 1976

[14] C Cuello P Correa W Haenszel et al ldquoGastric cancer inColombia I Cancer risk and suspect environmental agentsrdquoJournal of the National Cancer Institute vol 57 no 5 pp 1015ndash1020 1976

[15] W Haenszel P Correa C Cuello et al ldquoGastric cancer inColombia II Case control epidemiologic study of precursorlesionsrdquo Journal of the National Cancer Institute vol 57 no 5pp 1021ndash1026 1976

[16] P Correa W Haenszel C Cuello et al ldquoGastric precancerousprocess in a high risk population cohort follow-uprdquo CancerResearch vol 50 no 15 pp 4737ndash4740 1990

[17] H Ohata S Kitauchi N Yoshimura et al ldquoProgression ofchronic atrophic gastritis associated with Helicobacter pyloriinfection increases risk of gastric cancerrdquo International Journalof Cancer vol 109 no 1 pp 138ndash143 2004

[18] V Conteduca D Sansonno G Lauletta S Russi G Ingravalloand F Dammacco ldquoH pylori infection and gastric cancer stateof the art (Review)rdquo International Journal of Oncology vol 42no 1 pp 5ndash18 2013

[19] C A Gonzalez and A Agudo ldquoCarcinogenesis prevention andearly detection of gastric cancer where we are and where weshould gordquo International Journal of Cancer vol 130 no 4 pp745ndash753 2012

[20] P Correa and M B Piazuelo ldquoThe gastric precancerous cas-caderdquo Journal of Digestive Diseases vol 13 no 1 pp 2ndash9 2012

[21] R M Delahay and M Rugge ldquoPathogenesis of Helicobacterpylori infectionrdquo Helicobacter vol 17 supplement 1 pp 9ndash152012

[22] C A Gonzalez C Figueiredo C B Lic et al ldquoHelicobacterpylori cagA and vacA genotypes as predictors of progression ofgastric preneoplastic lesions a long-term follow-up in a high-risk area in Spainrdquo American Journal of Gastroenterology vol106 no 5 pp 867ndash874 2011

[23] E P Saraga D Gardiol and J Costa ldquoGastric dysplasia Ahistological follow-up studyrdquo American Journal of SurgicalPathology vol 11 no 10 pp 788ndash796 1987

[24] M J Coma del Corral F J Pardo-Mindan S Razquin and COjeda ldquoRisk of cancer in patients with gastric dysplasia follow-up study of 67 patientsrdquo Cancer vol 65 no 9 pp 2078ndash20851990

[25] H K Koch M Oehlert and W Oehlert ldquoAn evaluation ofgastric dysplasia in the years 1986 and 1987rdquo Pathology Researchand Practice vol 186 no 1 pp 80ndash84 1990

[26] J L Whiting A Sigurdsson D C Rowlands M T Hallisseyand J W L Fielding ldquoThe long term results of endoscopicsurveillance of premalignant gastric lesionsrdquo Gut vol 50 no3 pp 378ndash381 2002

[27] M Rugge M Cassaro F Di Mario et al ldquoThe long term out-come of gastric non-invasive neoplasiardquo Gut vol 52 no 8 pp1111ndash1116 2003

[28] KC R B RamesarD SA Sanders andDHopwood ldquoLimitedvalue of type III intestinalmetaplasia in predicting risk of gastriccarcinomardquo Journal of Clinical Pathology vol 40 no 11 pp1287ndash1290 1987

8 Gastroenterology Research and Practice

[29] S Silva M I Filipe and A Pinho ldquoVariants of intestinalmetaplasia in the evolution of chronic atrophic gastritis andgastric ulcer A follow up studyrdquo Gut vol 31 no 10 pp 1097ndash1104 1990

[30] T Rokkas M I Filipe and G E Sladen ldquoDetection of anincreased incidence of early gastric cancer in patients withintestinal metaplasia type III who are closely followed uprdquo Gutvol 32 no 10 pp 1110ndash1113 1991

[31] J M Conchillo G Houben A de Brune and R StockbruggerldquoIs type III intestinal metaplasia an obligatory precancerouslesion in intestinal-type gastric carcinomardquo European Journalof Cancer Prevention vol 10 no 4 pp 307ndash312 2001

[32] L Vannella E Lahner and B Annibale ldquoRisk for gastricneoplasias in patients with chronic atrophic gastritis a criticalreappraisalrdquo World Journal of Gastroenterology vol 18 no 12pp 1279ndash1285 2012

[33] M Rugge A Meggio G Pennelli et al ldquoGastritis staging inclinical practice the OLGA staging systemrdquo Gut vol 56 no 5pp 631ndash636 2007

[34] L G Capelle A C de Vries J Haringsma et al ldquoThe staging ofgastritis with the OLGA system by using intestinal metaplasiaas an accurate alternative for atrophic gastritisrdquoGastrointestinalEndoscopy vol 71 no 7 pp 1150ndash1158 2010

[35] M Rugge M de Boni G Pennelli et al ldquoGastritis OLGA-staging and gastric cancer risk a twelve-year clinico-patholog-ical follow-up studyrdquo Alimentary Pharmacology and Therapeu-tics vol 31 no 10 pp 1104ndash1111 2010

[36] M Rugge J G Kim V Mahachai et al ldquoOLGA gastritisstaging in young adults and country-specific gastric cancerriskrdquo International Journal of Surgical Pathology vol 16 no 2pp 150ndash154 2008

[37] G N Stemmermann ldquoIntestinal metaplasia of the stomach Astatus reportrdquo Cancer vol 74 no 2 pp 556ndash564 1994

[38] M Rugge M Fassan M Pizzi G Pennelli D Nitti and FFarinati ldquoOperative Link for Gastritis Assessment gastritisstaging incorporates intestinal metaplasia subtypingrdquo HumanPathology vol 42 no 10 pp 1539ndash1544 2011

[39] M Rugge P Correa M F Dixon et al ldquoGastric mucosal atro-phy interobserver consistency using new criteria for classifica-tion and gradingrdquo Alimentary Pharmacology and Therapeuticsvol 16 no 7 pp 1249ndash1259 2002

[40] W Yasui K Sentani N Sakamoto K Anami Y Naito andN Oue ldquoMolecular pathology of gastric cancer research andpracticerdquo Pathology Research and Practice vol 207 no 10 pp608ndash612 2011

[41] C O Gigek E S Chen D Q Calcagno F Wisnieski R RBurbano and M A Smith ldquoEpigenetic mechanisms in gastriccancerrdquo Epigenomics vol 4 no 3 pp 279ndash294 2012

[42] A H Corvalan and M J Maturana ldquoRecent patents of DNAmethylation biomarkers in gastrointestinal oncologyrdquo RecentPatents on DNA and Gene Sequences vol 4 no 3 pp 202ndash2092010

[43] C Zhao and X Bu ldquoPromoter methylation of tumor-relatedgenes in gastric carcinogenesisrdquo Histology and Histopathologyvol 27 no 10 pp 1271ndash1282 2012

[44] A O O Chan S K Lam B C YWong et al ldquoPromotermethy-lation of E-cadherin gene in gastric mucosa associated withHelicobacter pylori infection and in gastric cancerrdquoGut vol 52no 4 pp 502ndash506 2003

[45] A O O Chan and A Rashid ldquoCpG island methylation inprecursors of gastrointestinal malignanciesrdquo Current MolecularMedicine vol 6 no 4 pp 401ndash408 2006

[46] T Maekita K Nakazawa M Mihara et al ldquoHigh levels of aber-rant DNA methylation in Helicobacter pylori-infected gastricmucosae and its possible association with gastric cancer riskrdquoClinical Cancer Research vol 12 no 3 part 1 pp 989ndash995 2006

[47] R Ohki J Nemoto H Murasawa et al ldquoReprimo a new can-didate mediator of the p53-mediated cell cycle arrest at the G2phaserdquoThe Journal of Biological Chemistry vol 275 no 30 pp22627ndash22630 2000

[48] B G Schneider D F Peng M C Camargo et al ldquoPromoterDNAhypermethylation in gastric biopsies from subjects at highand low risk for gastric cancerrdquo International Journal of Cancervol 127 no 11 pp 2588ndash2597 2010

[49] C Bernal F Aguayo C Villarroel et al ldquoReprimo as a potentialbiomarker for early detection in gastric cancerrdquo Clinical CancerResearch vol 14 no 19 pp 6264ndash6269 2008

[50] N S Sapari M Loh A Vaithilingam and R Soong ldquoClinicalpotential of DNA methylation in gastric cancer a meta-analysisrdquo PLoS One vol 7 no 4 Article ID e36275 2012

[51] G Carrasco J Diaz J R Valbuena et al ldquoOverexpression ofp73 as a tissue marker for high-risk gastritisrdquo Clinical CancerResearch vol 16 no 12 pp 3253ndash3259 2010

[52] D Faratian ldquoSystems pathologyrdquo Breast Cancer Research vol12 supplement 4 article S4 2010

[53] A I Saeed N K Bhagabati J C Braisted et al ldquoTM4microar-ray software suiterdquoMethods in Enzymology vol 411 pp 134ndash1932006

Submit your manuscripts athttpwwwhindawicom

Stem CellsInternational

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

MEDIATORSINFLAMMATION

of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Behavioural Neurology

EndocrinologyInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Disease Markers

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

BioMed Research International

OncologyJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Oxidative Medicine and Cellular Longevity

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

PPAR Research

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Immunology ResearchHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Journal of

ObesityJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Computational and Mathematical Methods in Medicine

OphthalmologyJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Diabetes ResearchJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Research and TreatmentAIDS

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Gastroenterology Research and Practice

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Parkinsonrsquos Disease

Evidence-Based Complementary and Alternative Medicine

Volume 2014Hindawi Publishing Corporationhttpwwwhindawicom

8 Gastroenterology Research and Practice

[29] S Silva M I Filipe and A Pinho ldquoVariants of intestinalmetaplasia in the evolution of chronic atrophic gastritis andgastric ulcer A follow up studyrdquo Gut vol 31 no 10 pp 1097ndash1104 1990

[30] T Rokkas M I Filipe and G E Sladen ldquoDetection of anincreased incidence of early gastric cancer in patients withintestinal metaplasia type III who are closely followed uprdquo Gutvol 32 no 10 pp 1110ndash1113 1991

[31] J M Conchillo G Houben A de Brune and R StockbruggerldquoIs type III intestinal metaplasia an obligatory precancerouslesion in intestinal-type gastric carcinomardquo European Journalof Cancer Prevention vol 10 no 4 pp 307ndash312 2001

[32] L Vannella E Lahner and B Annibale ldquoRisk for gastricneoplasias in patients with chronic atrophic gastritis a criticalreappraisalrdquo World Journal of Gastroenterology vol 18 no 12pp 1279ndash1285 2012

[33] M Rugge A Meggio G Pennelli et al ldquoGastritis staging inclinical practice the OLGA staging systemrdquo Gut vol 56 no 5pp 631ndash636 2007

[34] L G Capelle A C de Vries J Haringsma et al ldquoThe staging ofgastritis with the OLGA system by using intestinal metaplasiaas an accurate alternative for atrophic gastritisrdquoGastrointestinalEndoscopy vol 71 no 7 pp 1150ndash1158 2010

[35] M Rugge M de Boni G Pennelli et al ldquoGastritis OLGA-staging and gastric cancer risk a twelve-year clinico-patholog-ical follow-up studyrdquo Alimentary Pharmacology and Therapeu-tics vol 31 no 10 pp 1104ndash1111 2010

[36] M Rugge J G Kim V Mahachai et al ldquoOLGA gastritisstaging in young adults and country-specific gastric cancerriskrdquo International Journal of Surgical Pathology vol 16 no 2pp 150ndash154 2008

[37] G N Stemmermann ldquoIntestinal metaplasia of the stomach Astatus reportrdquo Cancer vol 74 no 2 pp 556ndash564 1994

[38] M Rugge M Fassan M Pizzi G Pennelli D Nitti and FFarinati ldquoOperative Link for Gastritis Assessment gastritisstaging incorporates intestinal metaplasia subtypingrdquo HumanPathology vol 42 no 10 pp 1539ndash1544 2011

[39] M Rugge P Correa M F Dixon et al ldquoGastric mucosal atro-phy interobserver consistency using new criteria for classifica-tion and gradingrdquo Alimentary Pharmacology and Therapeuticsvol 16 no 7 pp 1249ndash1259 2002

[40] W Yasui K Sentani N Sakamoto K Anami Y Naito andN Oue ldquoMolecular pathology of gastric cancer research andpracticerdquo Pathology Research and Practice vol 207 no 10 pp608ndash612 2011

[41] C O Gigek E S Chen D Q Calcagno F Wisnieski R RBurbano and M A Smith ldquoEpigenetic mechanisms in gastriccancerrdquo Epigenomics vol 4 no 3 pp 279ndash294 2012

[42] A H Corvalan and M J Maturana ldquoRecent patents of DNAmethylation biomarkers in gastrointestinal oncologyrdquo RecentPatents on DNA and Gene Sequences vol 4 no 3 pp 202ndash2092010

[43] C Zhao and X Bu ldquoPromoter methylation of tumor-relatedgenes in gastric carcinogenesisrdquo Histology and Histopathologyvol 27 no 10 pp 1271ndash1282 2012

[44] A O O Chan S K Lam B C YWong et al ldquoPromotermethy-lation of E-cadherin gene in gastric mucosa associated withHelicobacter pylori infection and in gastric cancerrdquoGut vol 52no 4 pp 502ndash506 2003

[45] A O O Chan and A Rashid ldquoCpG island methylation inprecursors of gastrointestinal malignanciesrdquo Current MolecularMedicine vol 6 no 4 pp 401ndash408 2006

[46] T Maekita K Nakazawa M Mihara et al ldquoHigh levels of aber-rant DNA methylation in Helicobacter pylori-infected gastricmucosae and its possible association with gastric cancer riskrdquoClinical Cancer Research vol 12 no 3 part 1 pp 989ndash995 2006

[47] R Ohki J Nemoto H Murasawa et al ldquoReprimo a new can-didate mediator of the p53-mediated cell cycle arrest at the G2phaserdquoThe Journal of Biological Chemistry vol 275 no 30 pp22627ndash22630 2000

[48] B G Schneider D F Peng M C Camargo et al ldquoPromoterDNAhypermethylation in gastric biopsies from subjects at highand low risk for gastric cancerrdquo International Journal of Cancervol 127 no 11 pp 2588ndash2597 2010

[49] C Bernal F Aguayo C Villarroel et al ldquoReprimo as a potentialbiomarker for early detection in gastric cancerrdquo Clinical CancerResearch vol 14 no 19 pp 6264ndash6269 2008

[50] N S Sapari M Loh A Vaithilingam and R Soong ldquoClinicalpotential of DNA methylation in gastric cancer a meta-analysisrdquo PLoS One vol 7 no 4 Article ID e36275 2012

[51] G Carrasco J Diaz J R Valbuena et al ldquoOverexpression ofp73 as a tissue marker for high-risk gastritisrdquo Clinical CancerResearch vol 16 no 12 pp 3253ndash3259 2010

[52] D Faratian ldquoSystems pathologyrdquo Breast Cancer Research vol12 supplement 4 article S4 2010

[53] A I Saeed N K Bhagabati J C Braisted et al ldquoTM4microar-ray software suiterdquoMethods in Enzymology vol 411 pp 134ndash1932006

Submit your manuscripts athttpwwwhindawicom

Stem CellsInternational

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

MEDIATORSINFLAMMATION

of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Behavioural Neurology

EndocrinologyInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Disease Markers

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

BioMed Research International

OncologyJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Oxidative Medicine and Cellular Longevity

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

PPAR Research

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Immunology ResearchHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Journal of

ObesityJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Computational and Mathematical Methods in Medicine

OphthalmologyJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Diabetes ResearchJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Research and TreatmentAIDS

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Gastroenterology Research and Practice

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Parkinsonrsquos Disease

Evidence-Based Complementary and Alternative Medicine

Volume 2014Hindawi Publishing Corporationhttpwwwhindawicom

Submit your manuscripts athttpwwwhindawicom

Stem CellsInternational

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

MEDIATORSINFLAMMATION

of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Behavioural Neurology

EndocrinologyInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Disease Markers

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

BioMed Research International

OncologyJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Oxidative Medicine and Cellular Longevity

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

PPAR Research

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Immunology ResearchHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Journal of

ObesityJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Computational and Mathematical Methods in Medicine

OphthalmologyJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Diabetes ResearchJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Research and TreatmentAIDS

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Gastroenterology Research and Practice

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Parkinsonrsquos Disease

Evidence-Based Complementary and Alternative Medicine

Volume 2014Hindawi Publishing Corporationhttpwwwhindawicom